Updated January 17, 2022 at 2:18 AM ET
The man who took hostages at a Texas synagogue on Saturday and died after a stand-off with police was 44-year-old British citizen Malik Faisal Akram, the FBI said in a statement on Sunday.
There was "no indication" that other individuals were involved in the incident, the bureau added.
The 10-hour standoff in the city of Colleyville, just outside of Fort Worth, ended when a hostage rescue team breached the synagogue and saved the three hostages. One other hostage had been freed earlier.
Akram died on the scene, though the FBI did not say how.
The synagogue's rabbi, Charlie Cytron-Walker, credited security trainings for helping him and the other hostages survive the encounter.
"Over the years, my congregation and I have participated in multiple security courses from the Colleyville Police Department, the FBI, the Anti-Defamation League, and Secure Community Network. We are alive today because of that education," said Cytron-Walker in a statement.
"I encourage all Jewish congregations, religious groups, schools, and others to participate in active-shooter and security courses."
The most recent training in August was by the Secure Community Network, a nonprofit that works with synagogues and Jewish communities to develop safety plans. It included active shooter training and inspection of the synagogue's perimeter and safety protocols, The Washington Post reported. It was the third training by the Secure Community Network last year.
Police in the U.K. detained two teenagers in connection with the incident on Sunday. Counterterrorism police arrested the two in South Manchester and they remain in custody for questioning, the Greater Manchester Police said. U.K. police said Akram was originally from the Blackburn area of Lancashire, which is to the north of Manchester.
U.K. police said they were assisting U.S. law enforcement in the investigation.
In a statement posted on a Facebook page for the Blackburn Muslim Community, Akram's brother Gulbar said that Akram suffered from mental health issues and that the family had been "liaising with Faisal, negotiators, FBI ..." throughout the incident.
In the statement, the brother maintained that hostages were "released from the fire exit and Not rescued."
""We would also like to add that any attack on any human being be it a Jew, Christian, or Muslim etc is wrong and should always be condemned. It is absolutely inexcusable for a Muslim to attack a Jew or for any Jew to attack a Muslim, Christian, Hindu, vice versa etc etc," the statement, which has since been deleted, read.
'This was an act of terror'
President Joe Biden said during a visit to Philadelphia on Sunday that the incident was an "act of terror" and condemned antisemitism.
"I wanted to make sure we got the word out to synagogues and places of worship that we're not going to tolerate this," said Biden, who also praised the efforts of federal and local law enforcement.
The hostage taker could be heard on a Facebook livestream of the Shabbat service demanding the release of Aafia Siddiqui, a Pakistani neuroscientist serving an 86-year sentence in a Texas federal prison, The Associated Press reported.
FBI confirmed that Akram spoke repeatedly about Siddiqui during negotiations with law enforcement, in a statement released Monday morning.
Anna Eisen, one of the founding members of the Congregation Beth Israel synagogue, told Weekend Edition that she turned on the livestream from home when she heard what was happening.
"I stayed glued to the computer. At times I really felt like I wanted to walk away," she said. "It was so terrifying, because everything was live and people's lives were at stake and every minute could have been that things would turn in a bad direction."
Eisen said the synagogue takes security seriously and has a close relationship with local law enforcement.
"Just like other government institutions, churches, synagogues, public schools, this has become part of the everyday operations ... to just be aware and be prepared," she said.
The synagogue's rabbi, Charlie Cytron-Walker, was reported to be one of the hostages. He wrote on Facebook on Sunday:
I am thankful and filled with appreciation for
All of the vigils and prayers and love and support,
All of the law enforcement and first responders who cared for us,
All of the security training that helped save us.
I am grateful for my family.
I am grateful for the CBI Community, the Jewish Community, the Human Community.
I am grateful that we made it out.
I am grateful to be alive.
Officials in the United Kingdom condemned the violence and expressed solidarity with the U.S. after learning the news that the hostage taker was a British citizen.
"My thoughts are with the Jewish community and all those affected by the appalling act in Texas. We condemn this act of terrorism and anti-semitism," Liz Truss, the U.K.'s Foreign Secretary, said in a tweet.
"We stand with US in defending the rights and freedoms of our citizens against those who spread hate."
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