COLLEYVILLE: The hostage-taker who held several hostages inside a Texas synagogue has been pronounced dead, according to law enforcement officials.

Speaking to reporters in Colleyville, FBI Dallas Special Agent in Charge Matthew DeSarno declined to identify the hostage-taker, but said the FBI had launched a global inquiry, involving investigators in Great Britain and Israel.

The synagogue's rabbi was one of the hostages, according to Colleyville Chief of Police Michael Miller.

Authorities are still trying to discern a precise motive for the attack.

The hostage-taker was heard demanding the release of Aafia Siddiqui, the Pakistani neuroscientist suspected of having ties to al-Qaida, the officials said.

He also said he wanted to be able to speak with her, according to the officials. Siddiqui is in federal prison in Texas.

The officials said investigators have not positively identified the man and cautioned that the information was based on a preliminary investigation.