The FBI described last weekend's thwarted attack on a Texas synagogue as a "hate crime and an act of terrorism" in which the four former hostages were cast as "heroes."
Dallas FBI chief Matthew DeSarno said the assailant Malik Faisal Akram, a British national, was killed by members of the bureau's Hostage Rescue Unit late Saturday during the raid on Congregation Beth Israel synagogue as the hostages ran from the building, 11 hours after the standoff began.
In the tense last hour of the standoff, DeSarno said the assailant had become increasingly incommunicative, alarming both law enforcement officials and the hostages. About the same time the FBI ordered its team into the building, DeSarno said the hostages, led by Rabbi Charlie Cytron-Walker, made their own decision to flee.
"The situation had gone from bad to significantly worse," DeSarno said. "They (the former hostages) are survivors and they are heroes."
DeSarno said Akram targeted the Colleyville, Texas synagogue because of its proximity to a Fort Worth federal prison where the assailant sought the release of convicted terrorist Aafia Siddiqui.
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Siddiqui, known as "Lady al Qaeda," was sentenced in 2010 to 86 years in prison for the attempted murder and assault of U.S. nationals and U.S. officers and employees in Afghanistan.
At Friday's briefing, Cytron-Walker said that he and the three other hostages feared for their lives as it appeared that Akram was becoming further agitated.
Earlier this week, the rabbi said he hurled a chair at Akram just before he and the three others made a run for it.
Since last weekend, the federal investigation has reached into United Kingdom where British authorities have questioned the assailant's teen-age children.
Earlier Friday, Attorney General Merrick Garland lauded the "incredible bravery" of Rabbi Cytron-Walker and his congregants, adding that the federal investigation is "not done."
"The FBI is now working full time to determine whether this perpetrator acted alone or with others," the attorney general told the U.S. Conference of Mayors.
This article originally appeared on USA TODAY: FBI: Former Texas synagogue hostages 'heroes' in thwarted standoff