(CNN) The FBI on Sunday identified Malik Faisal Akram, a 44-year-old British national, as the man who held four people hostage at a Texas synagogue in an hours-long standoff Saturday before a rescue team entered the building and killed the suspect.
An FBI Hostage Rescue Team killed Akram after the hostages were released around 9 p.m. local time, the agency said. Crime scene investigators at the Beth Israel Congregation in Colleyville, Texas -- about 15 miles from Fort Worth -- recovered one firearm they believe belonged to Akram, a spokesperson for the Bureau of Alcohol, Tobacco, Firearms and Explosives told CNN.
"Prayers answered. All hostages are out alive and safe," Gov. Greg Abbott tweeted about 20 minutes after a large bang and gunfire were heard in the direction of the synagogue.
The resolution came nearly 11 hours after Akram entered the synagogue as it livestreamed its Sabbath morning service on Facebook and Zoom at around 11 a.m. Saturday, Colleyville Police Chief Michael Miller said. The livestream appeared to capture part of the incident before it was removed.
Four people, including Rabbi Charlie Cytron-Walker, were initially taken hostage. One hostage, a man, was released unharmed around 5 p.m., Colleyville Police Sgt. Dara Nelson said.
Cytron-Walker said the gunman became "increasingly belligerent and threatening" in the last hour of their hostage crisis.
In a statement to CNN, Cytron-Walker described the ordeal as a "traumatic experience." He said that he and the other hostages are alive today due to the multiple security courses his congregation has taken over the years.
"Without the instruction we received, we would not have been prepared to act and flee when the situation presented itself," Cytron-Walker said. "I encourage all Jewish congregations, religious groups, schools, and others to participate in active-shooter and security courses."
President Joe Biden told reporters Sunday authorities "just don't have enough facts" to speculate why a man targeted a Colleyville, Texas synagogue, taking four hostages Saturday, calling the standoff "an act of terror."
"I don't-- we don't have I don't think there is sufficient information to know about why he targeted that synagogue, why he insisted on the release of someone who's been in prison for over 10 years, why he was engaged, why he was using an anti-Semitic and anti-Israeli comments," Biden told reporters.
Akram arrived in the United States approximately five weeks ago, landing at New York's JFK Airport, a law enforcement source familiar with the investigation told CNN.
He arrived legally in December, a separate federal law enforcement source told CNN. Therefore, Akram cleared vetting prior to his arrival, which would have been checked against classified and unclassified information available at the time.
Akram was not on a US government watchlist, the law enforcement source said.
A review conducted thus far of U.S. intelligence community databases containing terror-related threat information shows no prior derogatory information on Akram, according to the official.
British intelligence officials have advised their US counterparts that a preliminary review of their databases similarly show no derogatory information about Akram, the source said. UK authorities are continuing to scrub their systems.
UK Counter Terrorism Police for Greater Manchester announced on Sunday the detention of two teenagers in connection with the hostage incident. Both individuals, who were arrested in South Manchester, are still in custody for questioning.
Authorities are still trying to figure out how Akram traveled to Texas.
Akram spent three nights at Union Gospel Mission Dallas, a homeless shelter, in the week prior to the incident, according to shelter CEO Bruce Butler.
"We were a way station for him. He had a plan. He was very quiet. He was in and out," Butler told CNN in a phone call Sunday.
Butler said Akram initially checked in to the shelter on January 6, before checking out and checking back in multiple times over the course of a week.
He left the facility for the final time on January 13, according to Butler, a little more than 48 hours before taking four people hostage inside the synagogue approximately 22 miles away.
Butler couldn't gather much about Akram's personality and said there was not anything obvious or revealing regarding Akram's personal religious beliefs.
Two law enforcement officials told CNN Saturday that investigators believe Akram may have been motivated by a desire to release Aafia Siddiqui, who is serving an 86-year sentence at a facility in Texas. She was convicted in 2010 on seven charges, including attempted murder and armed assault on US officers in Afghanistan.
"We do believe from our engaging with this subject that he was singularly focused on one issue, and it was not specifically related to the Jewish community, but we'll continue to work to find motive," DeSarno said.
Akram also told hostage negotiators that he was not going to leave the synagogue alive, a US law enforcement source familiar with the investigation told CNN.
The source said that during the conversation with the negotiators, Akram demanded that Siddiqui be brought to the synagogue so they could both die together.
"I just want a bullet in me, and I want to go -- that's it," Akram was heard saying in the livestream. Akram reiterated that sentiment in two telephone conversations picked up on the livestream.
"I'm gunned up. I'm ammo-ed up. Guess what, I will die," he told an individual he called nephew. He later told a second person who called him, "I am going to die, so don't cry for me."
Officials said it's believed Akram wanted Siddiqui released, based on both discussions with the suspect and audio heard on the synagogue's livestream.
The attorney who represents Siddiqui said Saturday "she has absolutely no involvement with" the taking of hostages at the synagogue and said the perpetrator is not Siddiqui's brother.
"She does not want any violence perpetrated against any human being, especially in her name," Marwa Elbially told CNN by phone. "It obviously has nothing to do with Dr. Siddiqui or her family."
At the request of the hostage taker, the rabbi of the congregation who was being held hostage called a well known rabbi in New York City, according to two officials briefed on investigation.
The FBI interviewed the New York City-based rabbi who spoke to the hostage taker earlier Saturday. The hostage taker, who has no connection with the rabbi, told her that Siddiqi was framed and he wants her released, the officials said.
Congregation Beth Israel is affiliated with the Union for Reform Judaism, whose website indicates the congregation serves 157 membership families.
The synagogue, established in 1999 with 25 membership families, was the first Jewish congregation in Northeast Tarrant County, according to CBI's website. The CBI community officially opened the doors to its own new building in 2005.
CBI holds Sabbath morning services every Saturday, and members and non-members alike are welcome to watch from home on the livestream, a practice many synagogues have adopted due to the Covid-19 pandemic.
In 2010, Siddiqui was sentenced to 86 years in prison by a New York federal judge following a 14-day trial. A jury found her guilty of the attempted murder of US nationals and government employees, as well as assault against US officers and employees.
Siddiqui -- a Pakistani scientist who graduated from the Massachusetts Institute of Technology and obtained a doctorate from Brandeis University -- was taken into custody for questioning by the Afghan National Police in 2008, who said they found handwritten notes referring to potential targets of a "mass casualty attack," according to a federal indictment.
When a group of Americans attempted to speak to her, prosecutors said she was able to grab a US soldier's rifle and open fire on the interrogation team, although no one was hit by the gunfire.
At sentencing, the judge found that a terrorism enhancement applied to her crimes, citing statements she had made that the judge concluded demonstrated her actions and intent to retaliate against the US government, including "I hate Americans" and "Death to America."
Her conviction has been the subject of regular protests in the US and overseas. Frequent demonstrations have been organized by the Aafia Foundation, a group named for her. That group has claimed that she was assaulted in prison last year.
Her family has said in interviews with CNN that she is not a terrorist.
During a deadly hostage crisis in Algeria in 2013, a spokesperson for a militant group offered to release hostages if Siddiqui was released from US prison, along with Sheikh Omar Abdel Rahman, the mastermind of the 1993 World Trade Center attack, who has since died in prison.
Siddiqui is being held in a medical facility that's part of a federal prison in Fort Worth, with a release date set for 60 years from now.