Prosecutors aren't asking for the maximum prison sentence for an American who played a central role in the 2008 terrorist attack in Mumbai, India, that left more than 160 people dead.

In federal court documents filed Tuesday in Chicago, prosecutors asked a judge to sentence David Coleman Headley to between 30 and 35 years in prison.

Headley was accused of conducing scouting missions ahead of the attack, which has been called India's 9/11. He was convicted on charges that carry a life sentence.

But prosecutors say he should be credited for "the significant value provided by his immediate and extensive cooperation" following his 2009 arrest.

They say the 52-year-old Headley provided "insight into the personnel, structure, methods, abilities and plans" of the Pakistani group that carried out the attack.