(CNN) The scene was a nightmare: After a long, televised police chase of a hijacked UPS truck ground to a halt at a jammed South Florida intersection, gunfire erupted seemingly from everywhere Thursday evening — with vehicles stopped at a traffic light serving as officers' impromptu shields.
Gunfire exploded toward and from the truck. A bystander crouched on a median, then scrambled away as officers closed in.
In the end, four people were shot dead at the intersection in Miramar, authorities said, including two robbery suspects, a bystander, and hostage UPS driver Frank Ordonez, a man who relatives say had been substituting for a colleague who had called out from work that day.
The slain robbers and hijackers were Lamar Alexander, 41, and Ronnie Jerome Hill, 41, both of Miami-Dade County, the FBI said.
The bystander who was killed was Richard Steven Cutshaw, according to the Broward County, Florida, medical examiner's office.
The union field representative was driving home from work when he was killed in the crossfire, said Don Slesnick, a lawyer for the Office and Professional Employees International Union where Cutshaw worked.
Slesnick said Cutshaw represented more 2,500 government employees in Broward County and Naples, helping them with insurance benefits, assignments, pay issues and negotiating contracts.
Known as "Rick" to his coworkers, Slesnick said he was good-humored and pleasant who was loved by all who worked with him.
"He fought with a positive attitude," Slesnick said.
The cause and manner of death of the four deceased were not released due to the active criminal investigation, the medical examiner said.
Numerous questions about the chase and its finale remain, including who shot Ordonez and Cutshaw.
Ordonez's stepfather said he can't understand why his stepson is dead.
"For this to happen, I think, is just unnecessary," Joe Merino told NBC's "Today" show Friday morning. "Other tactics should have been applied, and they weren't, so when I say the word devastated, it's an understatement."
A police union official, meanwhile, said that officers handled the situation well, given the circumstances.
"If you shoot at us, we are going to engage. We are going to stop the threat," Steadman Stahl, president of the South Florida Police Benevolent Association, said Friday. "When bad guys are shooting at you, how do you negotiate?"
The incident began with a jewelry store robbery late Thursday afternoon in Coral Gables, near Miami, authorities said.
Police got a call about a silent holdup alarm at 4:17 p.m. from Regent Jewelers in Coral Gables, city Police Chief Edward J. Hudak Jr. said. At least one woman was hurt in the robbery, police said.
The woman had surgery and was conscious Friday and "doing well," Hudak said. Police Director Juan Perez said she suffered a wound to the head.
The suspects then hijacked the UPS truck, took the driver hostage and sped away.
Soon after, police received a call of gunshots -- believed to have been fired by the escaping suspects, Hudak said -- at Coral Gables City Hall, just within sight of the jeweler's shop. A bullet struck the building, which went into lockdown.
The UPS truck then fled over at least 25 miles, through city streets and along an interstate. Police caught its trail, and some of their pursuit unfolded on local television as news helicopters captured the scenes from above.
Police radioed that gunfire occasionally erupted from the truck — its back doors sometimes open — even as police chased it on or near I-75, CNN affiliate WSVN reported.
The truck hopped curbs, spun U-turns and maneuvered around other vehicles and police.
Emergency vehicles trailed the hijacked truck, stretching at one point for about half a mile.
Then, as the truck approached the intersection of Miramar Parkway and Flamingo Road in Miramar around 5:35 p.m., the chase ground to a halt.
Traffic — including a light-colored SUV and, behind it, a dark-colored SUV — was stopped, and the UPS truck suddenly was boxed in. More than 40 emergency vehicles, their lights flashing, queued up in its wake.
Police officers left their vehicles and approached the UPS truck, weapons drawn. They used cars — their own and those that had been at the intersection — as shields so they could approach in a better position.
The person driving the UPS truck left the steering wheel.
Shots rang out, though who fired first — someone inside the truck or police — remains an open question.
Muzzle flashes could be seen inside the truck, helicopter footage from WSVN shows. Smoke began to rise.
Gunfire exploded, seemingly from everywhere, a video recorded by someone in a car and posted to Twitter shows.
A bystander in a median crouched, then scurried away as officers moved in all around, the video shows.
Chaos gripped the scene. The light-colored SUV, behind which at least three officers had taken cover, rolled forward, putting a stationary white van between it and the UPS truck, video from WSVN shows.
Then, the dark-colored SUV moved up, pushing into the lighter SUV's bumper. Officers took cover on the driver's side of that vehicle, WSVN video shows.
No more than a minute after the shootout started, bedlam turned to quiet. The truck's windshield bore marks from numerous bullets.
At least 13 police officers were shot at, but none was injured, said Stahl, the police union president.
Two or three bullets pierced the windshield of one officer's cruiser, Stahl said.
Whether the UPS driver and the slain bystander were shot by police is under investigation, FBI Special Agent in Charge George Piro said. The Bureau of Alcohol, Tobacco, Firearms and Explosives also is investigating, Hudak said.
"This is what dangerous people do to get away," Hudak, the Coral Gables police chief, told reporters Thursday. "And this is what dangerous people will do to avoid capture."