Inquiry into Texas synagogue standoff to have 'global reach'

US authorities have launched an investigation with "global reach" into a suspect who was killed after holding four people hostage at a Texas synagogue, where he apparently demanded the release of a convicted terrorist known as "Lady Al-Qaeda."

The four hostages -- including a respected local rabbi, Charlie Cytron-Walker -- were all released unharmed Saturday night, prompting relief in the United States, where the Jewish community and President Joe Biden renewed calls to fight anti-Semitism.

Police did not say whether the assault team killed the man or whether he killed himself.

"We'll investigate the hostage taker and his contact," FBI special agent Matt DeSarno told reporters in the small Texas town of Colleysville after the climactic end of the standoff.

"We'll have global reach. We have been in contact with multiple FBI leads to include Tel Aviv and London."

A spokesman for the Foreign Office in London confirmed no details but said in a statement that "we are aware of the death of a British man in Texas and are in contact with the local authorities."

DeSarno told the news conference the suspect had been identified, but did not disclose his identity.

Quoting a US official briefed on the matter, ABC reported the man was demanding the release of Aafia Siddiqui -- a Pakistani scientist who in 2010 was sentenced by a New York court to 86 years in prison for the attempted murder of US officers in Afghanistan.

Siddiqui is currently being held at a prison in Fort Worth, Texas.

In a statement to CNN, Siddiqui's lawyer said she "has absolutely no involvement" in the hostage situation and condemned it.

Siddiqui was the first woman suspected of links to Al-Qaeda to be arrested in the US, drawing the nickname "Lady Al-Qaeda."