DHAKA: Sulaiman Abu Ghaith, Osama bin Laden's son-in-law, was sentenced to life in prison Tuesday, said Jerika Richardson, a spokeswoman for the U.S. Attorney's Office in Manhattan.

In March, he was found guilty of helping al Qaeda terrorists conspire to kill Americans and providing material support to terrorists, reports the BBC.

"Justice has been served," U.S. Attorney General Eric Holder said in a statement. "This outcome ensures that Sulaiman Abu (Ghaith), a senior member of al Qaeda and an associate of Usama bin Laden, will never again set foot outside a prison cell."

The life term was imposed by U.S. District Judge Lewis A. Kaplan. Authorities described Abu Ghaith as bin Laden's "propaganda minister" and the "face and voice of al Qaeda in the days and weeks after the 9/11 attacks."

At his trial, federal prosecutors said Abu Ghaith, a Kuwaiti cleric, played a crucial role as the organization's principal mouthpiece and recruiter, helping "restore al Qaeda's trove of new terrorists" as deadly missions turned its members into martyrs.

"He was more than just Usama bin Laden's propaganda minister. Within hours after the devastating 9/11 attacks, Abu Ghayth was using his position in al Qaeda's homicidal hierarchy to persuade others to pledge themselves to al Qaeda in the cause of murdering more Americans," Manhattan U.S. Attorney Preet Bharara said in a prepared statement after the guilty verdict was announced.

Abu Ghaith, 48, was flown to the United States a year ago from Jordan and charged with conspiring to kill Americans.

The government did not allege that he served an operational function or had a direct hand in carrying out the attacks.

Bharara said at the time of Abu Ghaith's conviction: "Like the others who have faced terrorism charges in Manhattan's federal courthouse before him, Abu Ghayth received a fair trial, after which a unanimous jury rendered its verdict, justly holding him accountable for his crimes. We hope this verdict brings some small measure of comfort to the families of the victims of al Qaeda's murderous designs."

In a statement, George Venizelos, assistant director in charge of the FBI's New York field office, likened Abu Ghaith to "a consigliere for the mob or the chief of staff to a corrupt foreign leader" and said he was a "spokesman, confidant and senior adviser" to bin Laden's organization.

Abu Ghaith "looked to better al Qaeda's reputation at every turn, offering advice and counsel to the organization's senior leadership. He encouraged others to abandon the true tenets of their faith, swearing bayat to the twisted ideology of al Qaeda," Venizelos said, using the Islamic word for allegiance.

The trial was held blocks from the site of Manhattan's World Trade Center, and several survivors of the attacks and family members of victims attended.

BDST: 1541 HRS, SEP 24, 2014