San Bernardino, California(CNN) Denise Peraza wasn't sure if the phone call to her sister might be her last. She had just been shot in the back.
"I just want to tell you that I love you," Peraza told Stephanie Baldwin through tears.
"And then she said she had to go and she hung up," Baldwin told CNN affiliate KABC.
Peraza -- who was treated at a local hospital and is expected to be OK -- was one of the people inside the Inland Regional Center in San Bernardino, California, Wednesday morning when two people barged into a holiday party and opened fire, killing at least 14 people and injuring 17 others.
"As soon as the gunfire started, everyone dropped to the floor and they were underneath desks, and she was trying to shield herself with a chair, along with a man next to her," said Baldwin. "Then, all of a sudden, she said she just felt (the bullet) going through her back."
Peraza, like others at the party, worked for the County Department of Environmental Health and was only at Inland Regional Center -- an agency for people with developmental disabilities -- for the holiday event, her relatives said.
Peraza's ordeal was just one of many that played out through hushed phone calls and hurried texts after police said shooter Syed Farook -- who was at the party and left after some kind of confrontation -- and Tashfeen Malik attacked the partygoers.
Survivors, relatives and other witnesses spoke of the harrowing moments.
'It was horrific'
Social worker Melinda Rivas was working on the third floor of Building 2 of Inland when a co-worker came running down the hallway shouting that a shooter was downstairs.
"We all started running and screaming," she said.
Rivas believed the shooting was in Building 3, where there's an auditorium that's not usually locked and where public health employees were holding a Christmas party. The auditorium is frequently rented out to outside agencies, she said.
Rivas and 46 other employees were told to go into a conference room, she said. "There's 47 of us, and we were told just to lay down, sit down, comfort each other and pray with each other."
She called her twin adult children, both 21, and told them about the shooter and to "be safe."
"It was horrific," Rivas said of the experience.
About 20 minutes later, authorities told the 47 people in the conference room to come out -- with their hands raised.
"We were all just scared to leave with our hands up," she said.
More than six hours later, after being interviewed by authorities, Rivas and scores of Inland employees were bused to the Rudy Hernandez Community Center to make a final checkout with officials.
On the bus ride to the center, a co-worker recounted to several people on the bus how he saw two gunmen enter Building 3 and begin firing on everybody without saying a word, said Rivas, who added that the co-worker's shirt was stained with blood.
"Pray for us"
All Terry Pettit could do was worry as he stood near the offices of Inland Regional Center.
News of shootings was spreading fast and all Pettit knew about his daughter inside the building came from her text messages on his cell phone.
"Shooting at my work. People shot."
"Pray for us. I am locked in an office."
Pettit wept for his daughter as he spoke Wednesday afternoon with reporters. Sirens blared in the background.
"She's been hiding," he said.
'There's a shooter @ work'
When the shots ran out at the Inland Regional Center, text messaging seemed the safest way to communicate.
Marcos Aguilera, 39, of Riverside, received a message from his wife, a social worker helping babies diagnosed with autism.
"There's a shooter @ work," Elaine Aguilera wrote.
"Where r u at," "R cops there?" and "R u safe," he wrote back.
"Locked in an office with 3 other people," she texted, and then added, "I love you."
Aguilera, who works in the finance department for the Riverside Superior Court, left work and sped to his wife's office.
Aguilera said his wife heard the gunfire that rang through the three-building complex near the Santa Ana River, with the San Bernardino Mountains in the distance.
"She heard the shots and (other people) crying," he said.
When someone pulled the fire alarm, many of the roughly 200 people at the facility became confused, Aguilera said.
A SWAT team eventually rescued his wife and two other coworkers. At first she thought they were the attackers. As she walked out, she saw multiple bodies on the floor, Aguilera said.
"I've been wondering who would shoot up a building like that ... someone who's helping kids," he said. "I just don't know. People are crazy nowadays."
Rudy Peralta got a text message from his wife, Christina Gonzalez-Peralta, another social worker at Inland Regional Center.
She tweeted, "Check the news. Not sure if we're having an active shooter."
Gonzalez-Peralta and 12 coworkers found a file room as refuge, and they felt safe there because it was not well-known, Rudy Peralta said. But when someone suggested that they move furniture to barricade the door, the other employees were too terrified to move.
"Everyone was too scared. 'I said keep quiet and don't make noise,'" Rudy Peralta said, recounting his text message to his wife.
The 13 hid for more than half an hour until authorities rescued them.
As he recounted his wife's story, Rudy Peralta said he had just heard on the radio that the suspects were in a standoff with authorities. "I heard they caught them," Rudy Peralta added. "I'm anxious to see her and make sure she is OK."
Then his wife called.
"That's the first time I talked to her," said her visibly happy husband.
"She just feels relieved now," said Peralta. "You hear it on the news, but you never think it would hit so close to home."
What those near shootout saw, heard
A swarm of police and SWAT officers looked for those behind the massacre, focusing on a six-block residential area of San Bernardino.
Mahir, who asked his first name only be used, told CNN's Erin Burnett about what it was like to be near the police shootout with possible suspects.
"We didn't see much of anything. We just heard so many gunshots, it's crazy," he said. "Right now, everything seems to be cooled down. We just saw so many SWAT and cops and cop cars, at least a dozen or so."
Norman Rodgers, who lives on the street where the shootout occurred, said he was in his back yard checking on plants when he heard a "barrage of bullets." He estimated that to be between 100 and 200 rounds.
"That got me in the house real quick. On the floor. In the den. There were policemen everywhere."
Alan Ayers was catching a bus in the area when he heard the shooting.
"It was rapid boom, boom, boom, boom," he told CNN affiliate KCBS. "I was behind the building, and I heard all the shots."
'We thought it was a fire drill'
The executive director of the Inland Regional Center, Lavinia Johnson, told CNN when the shooting started staff and clients remained in locked offices until police arrived.
San Bernardino shooting
Police officers stand guard as they investigate a suspicious vehicle in Redlands, California, on Wednesday, December 2, after a mass shooting in nearby San Bernardino in which 14 people died and 21 were injured. The shooting took place at the Inland Regional Center, where employees with the county health department were attending a holiday event. The two shooters -- Syed Rizwan Farook and his wife, Tashfeen Malik -- were fatally shot in a gun battle with police hours after the initial incident. Farook worked for the county health department.
A police officer places a marker along East San Bernardino Avenue, near where the shootout occurred.
Law enforcement officers search a residential area for suspects who fled after the shooting.
Police search for the suspects in San Bernardino.
The residential area was not far from where the shooting occurred.
Law enforcement officers search a neighborhood in San Bernardino.
A police officer loads his weapon while pursuing suspects.
A SWAT team mobilizes during the search.
People pray on the San Bernardino Golf Course, across the street from where the shooting took place.
Heavily armed law enforcement officers swarmed the area where the shooting occurred.
People leave a community center after reuniting with friends and family in the aftermath of the shootings.
A woman is comforted near the scene of the shooting.
A police helicopter hovers around the Inland Regional Center.
Luis Gutierrez gets emotional as he talks about his wife who works in the facility and saw a gunman, according to Los Angeles Times photographer Marcus Yam.
Two women speak with a firefighter at a triage area near the scene.
Police stand guard outside of the emergency room at the Loma Linda University Medical Center, where some of the victims were being treated.
Police escort civilians away from the site of the shooting.
People walk away from the scene. It is unclear how many people were at the facility at the time of the shooting.
Police in SWAT gear secure the area.
Two women embrace at a community center where family members were gathering to pick up people from the scene.
People gather at the San Bernardino Golf Course.
People talk to police at the golf course.
A woman is wheeled away on a stretcher.
People are moved away from the area by bus.
Police and fire personnel are seen near the site of the shooting.
A crowd gathers behind the police line.
Ambulances pull out of a staging area near the Inland Regional Center.
A SWAT vehicle carries police officers.
SWAT teams and a bomb squad were working to clear the buildings where the shootings took place.
"As far as we know, we're all OK," she said, adding that center personnel were gathered in groups at a golf course across the street.
Johnson said a fire alarm was activated at the time of the shooting. Some people began evacuating.
"We thought it was a fire drill," she said. "We started to exit. ... We were told to go back into the building."
'Active shooter on site'
Scott and Deborah Murphy received a flurry of text messages from their daughter Megan, a processing clerk at the center.
Worst mass shootings in the United States
Parents wait for news after a shooting at Marjory Stoneman Douglas High School in Parkland, Florida, on Wednesday, February 14.
At least 17 people were killed at the school, Broward County Sheriff Scott Israel said. The suspect, 19-year-old former student Nikolas Cruz, is in custody, the sheriff said. The sheriff said he was expelled for unspecified disciplinary reasons.
Investigators at the scene of a mass shooting at the First Baptist Church in Sutherland Springs, Texas, on Sunday, November 5, 2017.
A man opened fire inside the small community church, killing at least 25 people and an unborn child. The gunman, 26-year-old Devin Patrick Kelley, was found dead in his vehicle. He was shot in the leg and torso by an armed citizen, and he had a self-inflicted gunshot to the head, authorities said.
A couple huddles after shots rang out at a country music festival on the Las Vegas Strip on Sunday, October 1, 2017. At least 58 people were killed and almost 500 were injured when
a gunman opened fire on the crowd. Police said the gunman, 64-year-old Stephen Paddock, fired from the Mandalay Bay hotel, several hundred feet southwest of the concert grounds. He was found dead in his hotel room, and authorities believe he killed himself and that he acted alone. It is the deadliest mass shooting in modern US history.
Police direct family members away from the scene of a shooting at the Pulse nightclub in Orlando in June 2016. Omar Mateen, 29,
opened fire inside the club, killing at least 49 people and injuring more than 50. Police fatally shot Mateen during an operation to free hostages that officials say he was holding at the club.
In December 2015,
two shooters killed 14 people and injured 21 at the Inland Regional Center in San Bernardino, California, where employees with the county health department were attending a holiday event. The shooters, Syed Rizwan Farook and his wife Tashfeen Malik, were later killed in a shootout with authorities. The pair were found to be radicalized extremists who planned the shootings as a terror attack, investigators said.
Police search students outside Umpqua Community College after
a deadly shooting at the school in Roseburg, Oregon, in October 2015. Nine people were killed and at least nine were injured, police said. The gunman, Chris Harper-Mercer, committed suicide after exchanging gunfire with officers, a sheriff said.
A man kneels across the street from the historic Emanuel African Methodist Episcopal Church in Charleston, South Carolina,
following a shooting in June 2015. Police say the suspect, Dylann Roof, opened fire inside the church, killing nine people. According to police, Roof confessed and told investigators he wanted to start a race war.
He was eventually convicted of murder and hate crimes, and a jury recommended the death penalty.
Police officers walk on a rooftop at the Washington Navy Yard after a
shooting rampage in the nation's capital in September 2013. At least 12 people and suspect Aaron Alexis were killed, according to authorities.
Connecticut State Police evacuate
Sandy Hook Elementary School in Newtown, Connecticut, in December 2012. Adam Lanza opened fire in the school, killing 20 children and six adults before killing himself. Police said he also shot and killed his mother in her Newtown home.
James Holmes pleaded not guilty by reason of insanity to a July 2012 shooting at a movie theater in Aurora, Colorado. Twelve people were killed and dozens were wounded when Holmes opened fire during the midnight premiere of "The Dark Knight Rises." He was sentenced to 12 life terms plus thousands of years in prison.
A military jury convicted Army Maj.
Nidal Hasan of 13 counts of premeditated murder for a November 2009 shooting rampage at Fort Hood, Texas. Thirteen people died and 32 were injured.
Jiverly Wong shot and killed 13 people at the American Civic Association in Binghamton, New York, before turning the gun on himself in April 2009, police said. Four other people were injured at the
immigration center shooting. Wong had been taking English classes at the center.
Pallbearers carry a casket of one of
Michael McLendon's 10 victims. McLendon shot and killed his mother in her Kingston, Alabama, home, before shooting his aunt, uncle, grandparents and five more people. He shot and killed himself in Samson, Alabama, in March 2009.
Virginia Tech student Seung-Hui Cho went on a shooting spree on the school's campus in April 2007. Cho killed two people at the West Ambler Johnston dormitory and, after chaining the doors closed, killed another 30 at Norris Hall, home to the Engineering Science and Mechanics Department. He wounded an additional 17 people before killing himself.
Mark Barton walked into two Atlanta trading firms and fired shots in July 1999, leaving nine dead and 13 wounded, police said. Hours later, police found Barton at a gas station in Acworth, Georgia, where he pulled a gun and killed himself. The day before, Barton had bludgeoned his wife and his two children in their Stockbridge, Georgia, apartment, police said.
Eric Harris, left, and Dylan Klebold brought guns and bombs to
Columbine High School in Littleton, Colorado, in April 1999. The students gunned down 13 and wounded 23 before killing themselves.
In October 1991,
George Hennard crashed his pickup through the plate-glass window of Luby's Cafeteria in Killeen, Texas, before shooting 23 people and committing suicide.
James Huberty shot and killed 21 people, including children, at a McDonald's in San Ysidro, California, in July 1984. A police sharpshooter killed Huberty an hour after the rampage began.
Prison guard George Banks is led through the Luzerne County courthouse in 1985. Banks killed 13 people, including five of his children, in Wilkes-Barre, Pennsylvania, in September 1982. He was sentenced to death in 1993 and received a stay of execution in 2004. His death sentence was overturned in 2010.
Officers in Austin, Texas, carry victims across the University of Texas campus after Charles Joseph Whitman opened fire from the school's tower, killing 16 people and wounding 30 in 1966. Police officers shot and killed Whitman, who had killed his mother and wife earlier in the day.
Howard Unruh, a World War II veteran, shot and killed 13 of his neighbors in Camden, New Jersey, in 1949. Unruh barricaded himself in his house after the shooting. Police overpowered him the next day. He was ruled criminally insane and committed to a state mental institution.
"Active shooter on site. We're all locked in offices and on the floor. Please pray for us," Megan Murphy wrote.
"So, as a parent, as a father, that's kind of like the worst thing that you can have come across your phone," Scott Murphy told CNN.
"Then it was followed a couple minutes later with, 'SWAT team is on site trying to secure the building. I'm in a tiny room with a bunch of people. We're freaking out. Please pray for us.'"
Later, the Murphys waited for their daughter to be interviewed by investigators.
"She's really sick," Deborah Murphy said. "She's dizzy. She's not feeling good ... Hopefully, they'll get her processed and we can get her back in our arms."
Triage stations
The area surrounding the center resembled a war zone, with dozens of people walking out of the building with their hands in the air and lines of heavily armed officers aiming their weapons. Some of the wounded were taken out on stretchers. Triage stations were set up outside.
Kristin Krause, who works at a charter school about a mile away, said the staff and 400 students were on lockdown.
The students were secure, she said.
"We have all gates locked. We are doing everything we can to make sure our kids are protected."
CNN's Ashley Fantz, Catherine E. Shoichet, Alberto Moya, Phil Gast, Melanie Whitley and Deborah Feyerick contributed to this report. Michael Martinez reported from San Bernardino and Ray Sanchez wrote from New York.