CHICAGO: An American was sentenced on Thursday to 35 years in prison for the key role he played in a 2008 terrorist attack on Mumbai that has been called India's 9/11.

David Coleman Headley's meticulous scouting missions facilitated the assault by 10 gunmen from a Pakistani-based militant group, which killed 160 people _ including children.

''I don't have any faith in Mr. Headley when he says he's a changed person and believes in the American way of life,'' said US District Judge Harry Leinenweber in imposing the sentence, which was in the range of what prosecutors had requested for Headley's widespread cooperation.

The attackers arrived by boat on Nov. 26, 2008, carrying grenades and automatic weapons, and fanned out to hit multiple targets, including a crowded train station, a Jewish center and the landmark Taj Mahal Hotel. TV cameras captured much of the three-day rampage live.

The attack heightened the strain in a historically antagonistic relationship between India and Pakistan, which have fought three major wars.

Indian officials accuse Pakistani intelligence of helping to plan the assault _ an allegation Pakistan denies.

The maximum sentence Headley, 52, faced Thursday was life in prison. He agreed to cooperate with US authorities and plead guilty in 2010 to 12 counts to avoid what would have been his maximum sentence: death. He also secured a promise not to be extradited to India.

Last year, India secretly hanged the lone surviving gunman, Mohammed Ajmal Kasab.

Citing what they described as valuable intelligence Headley provided authorities about terrorist networks since his arrest, prosecutors had asked for a relatively lenient sentence of between 30 and 35 years.

The charges included conspiracy to aid the Pakistani-based group, Lashkar-e-Taiba (LeT), that mounted the attacks, as well as conspiracy to commit murder in India and aiding and abetting in the murder of six Americans.