Joe Biden Vows To 'Stand Against' Anti-Semitism After Colleyville Hostage Standoff

President Joe Biden vowed the U.S. will stand against anti-Semitism and extremism, after an hourslong standoff with a man who took hostages a Texas synagogue.

The man took over services at Congregation Beth Israel in Colleyville on Saturday and was heard ranting and talking about religion on the synagogue's livestream.

"There is more we will learn in the days ahead about the motivations of the hostage taker," Biden said in a statement.

"But let me be clear to anyone who intends to spread hate—we will stand against anti-Semitism and against the rise of extremism in this country. That is who we are, and tonight, the men and women of law enforcement made us all proud."

One of the hostages was released during the standoff. Three others got out at about 9 p.m. local time (10 a.m. ET) when an FBI SWAT team entered the building.

Authorities said the hostage-taker was killed in a shooting, but did not answer questions about who shot the man.

Law enforcement sources confirmed to ABC News that the suspect was demanding the release of Aafia Siddiqui, who is incarcerated at Carswell Air Force Base near Fort Worth.