Even so, the U.S. intelligence official said Abu Ghaith probably has few details about ongoing terror threats or other current operational details to share with U.S. officials.
"We're not alleging that he was a planner, but a player within the group," the official said.
Abu Ghaith fled with bin Laden when the Taliban were ousted from power in Afghanistan in 2001, living for nearly a year in Afghanistan's northeastern Kunar province before crossing into Pakistan, according to Taliban officials familiar with his movements. Abu Ghaith operated between Pakistan's North Waziristan region and Middle Eastern countries, they said.
Prosecutors said Abu Ghaith was smuggled into Iran from Afghanistan in 2002. He lived there under house arrest until 2010.
At that time, Western officials say, Tehran brokered a deal with al-Qaida to release Iranian diplomat Heshmatollah Attarzadeh, who was kidnapped in 2008 in Pakistan's border city of Peshawar, in exchange for Abu Ghaith and several members of bin Laden's family, including one of his sons. That agreement also allowed al-Qaida access throughout Iran.
Lynch said it's believed that while living in Iran Abu Ghaith helped coordinate the flow of funding and foreign terror fighters in and out of Pakistan, Iraq and possibly Yemen.
"I know of nobody else we've captured who has spent as much time in the Iranian environment post-9/11, and we know there was a lot going on there helping facilitate this organization," said Lynch, a retired Army colonel who was a counterterror and South Asia adviser to former Joint Chiefs Chairman Adm. Mike Mullen and former Central Command chief Gen. John Abizaid.
Lynch said it's believed Abu Ghaith returned to Pakistan after leaving Iran but was uncomfortable there and sought to enter Turkey through Iran within the past several months. Tipped off by the CIA, Turkish officials took Abu Ghaith into custody but released him in late February without being able to charge him with a crime there. The intelligence official said Abu Ghaith was being deported to Kuwait when he stopped in Jordan. There, he was captured by the FBI and flown to the U.S. on March 1.
Abu Ghaith's family, including his wife, was allowed to continue on to Saudi Arabia, the intelligence official said.
As for the defendant's being tried in New York, Republican Sens. John McCain of Arizona, Lindsey Graham of South Carolina and Kelly Ayotte of New Hampshire said the White House's decision "will not go unchallenged."
"The Obama administration's lack of a war-time detention policy for foreign members of al-Qaida, as well as its refusal to detain and interrogate these individuals at Guantanamo, makes our nation less safe," the senators said in a statement. "A foreign member of al Qaida should never be treated like a common criminal and should never hear the words 'you have a right to remain silent.'"
White House spokesman Josh Earnest said security agencies across the government — including the departments of Justice, Homeland Security and Defense — agreed that Abu Ghaith would best be prosecuted in a federal court. Asked whether the top priority of detaining Abu Ghaith was to bring him to justice or gather intelligence, Josh Earnest said that federal courts could do both.
"We don't have to choose," Earnest said. "We're able to do both and that's exactly what we did."
Tom Hays reported from New York. Associated Press writers Larry Neumeister in New York and Kathy Gannon in Kabul, Afghanistan, contributed to this report.
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