Sulaiman Abu Ghaith, 48, Osama bin Laden's son-in-law and former al Qaeda spokesman, was sentenced to life in prison after being convicted by a U.S. jury of terrorism-related charges in March. During the sentencing, U.S. District Judge Lewis A. Kaplan said that Abu Ghaith showed "no remorse whatsoever," the Associated Press reports.

"At the same moment you were shackling my hands and intending to bury me alive, you are at the same time unleashing the hands of hundreds of Muslim youths. They will join the ranks of the free men soon, and very soon the world will see the end of these theater plays," said Abu Ghaith through an interpreter during sentencing in Federal District Court in Manhattan. He is the highest-ranking al Qaeda member to be put on trial in the U.S. since the Sept. 11, 2001, terrorist attacks, according to the AP.

During the three-week trial, videos made by Abu Ghaith were shown, some including threats of future attacks, or a "storm of airplanes," against the U.S. Abu Ghaith denied the allegations, saying he was serving a religious role, according to BBC.

Abu Ghaith's defense team had argued that he was potentially facing life in prison "for talk -- and only talk." Jurors deliberated for six hours before returning with guilty verdicts for conspiracy to kill Americans, providing material support to terrorists and conspiring to support terrorists.

Abu Ghaith was captured by the CIA in Jordan in March 2013. The former al Qaeda spokesman was arrested in Turkey and later deported to Kuwait. CIA agents seized Abu Ghaith in Jordan en route to Kuwait.

Sen. Lindsey O. Graham, R-S.C., said that Abu Ghaith should have been held by the military for "intelligence-gathering purposes."