Following the hours-long standoff at Congregation Beth Israel in Colleyville, Texas — about 15 miles northeast of Fort Worth — on Saturday that ended with the suspect, 44-year-old Malik Faisal Akram, dead and all hostages safe, the FBI has extended investigations to London and Tel Aviv to determine if he acted alone or with others.

Two teenagers had been detained in South Manchester as of Sunday evening in connection with the hostage incident, according to Greater Manchester Police. 

TEXAS SYNAGOGUE ACCUSED HOSTAGE TAKER WAS BRITISH NATIONAL  

Answering a question about the hostage incident before Parliament on Monday, U.K. Home Secretary Priti Patel said she had participated in a bilateral call with her counterpart at Homeland Security and has been working with the FBI. She vowed increased security for the Jewish community in the U.K.

"When it comes to our own domestic homeland, there are a range of measures being undertaken right now, including protective security for the Jewish community," she said. 

Matthew Offord, a conservative member of Parliament, pointed to a rise in antisemitic incidents in the Hendon constituency, and asked Patel for more security assurance. Patel said there are "watch lists" for antisemitic offenders and others, vowing the Jewish community is "fully supported." 

Akram could be heard on a Facebook live stream video demanding the release of an imprisoned Pakistani neuroscientist suspected of having ties to al Qaeda. Aafia Siddiqui, who is serving an 86-year prison sentence after being convicted in 2010 of trying to kill U.S. Army officers in Afghanistan, is being held at a federal prison in Fort Worth.

Malik Faisal Akram's brother, Gulbar Akram, raised questions in a recent interview with Sky News about how his sibling, given his criminal record, would have been allowed to obtain a visa and enter the U.S. 

The BBC reported, based on unnamed sources, that Malik Faisal Akram entered the U.S. two weeks ago through New York’s Kennedy Airport. Fox News Digital has not independently confirmed with the FBI how Malik Faisal Akram entered the U.S.   

Gulbar Akram has also placed blame for the incident on the suspect’s "mental health" issues. 

"He had mental health issues," he told The New York Times. "It’s well known, everybody in the town knows, he has mental health issues."

Faced with criticism for first expressing "condolences" over Malik Faisal Akram's death, the Blackburn Muslim Community apologized to the Jewish community for any offense. 

"We totally condemn any threats or attacks on innocent people," a statement shared to social media read. "We stand in solidarity with people of all faiths as we believe they are all free to practice their religious beliefs freely without the fear of being attacked. We have always promoted peace, love and harmony between people of all faiths and none." 

CLICK HERE TO GET THE FOX NEWS APP 

Condemning the "act of terror," President Biden remarked to reporters Sunday that it is believed the suspect had been staying at homeless shelters before the hostage incident in Colleyville. The president said it is also believed the suspect purchased the weapon used in the incident "on the street," though the attorney general’s office was still gathering information. 

Biden said he would have more information at a news conference Wednesday. 

The FBI has been criticized for its initial response to the incident. At first, the agency said the hostage standoff at the Texas synagogue was "not specifically related to the Jewish community." It then changed its tune, admitting it was a "terrorism-related matter, in which the Jewish community was targeted."