(CNN) -- A Chicago man received 35 years in prison on Thursday for his role in the deadly 2008 siege in Mumbai, India, that killed more than 160 people, including six Americans.
Federal prosecutors had asked U.S. District Judge Harry Leinenweber to sentence David Headley, 52, to 30-35 years behind bars rather than a full life sentence because he had been fully cooperative and provided useful intelligence after his arrest.
A Justice Department official who attended the hearing in Chicago said Headley had written a letter to the judge, but declined to speak in court.
Headley, who was born in Pakistan and changed his name from Daood Gilani, had lived much of his life in Chicago. But he attended terrorist training camps in Pakistan, authorities said.
He admitted scouting attack locations in Mumbai for the Pakistani terrorist group Lashkar-e-Tayyiba, which carried out the attack on the Taj Mahal Hotel and other targets over three days in November 2008.
Prosecutors said Headley also worked for members of al Qaeda.
Headley reached a plea agreement in 2010.