Image caption David Coleman Headley was arrested by FBI agents in Chicago in October 2009

A US man has been sentenced to 35 years in prison for his key role in plotting the deadly Mumbai attacks in 2008.

David Coleman Headley, 52, was sentenced on 12 counts, including conspiracy to aid militants from the Pakistani group Lashkar-e-Taiba (LeT) who carried out the attacks.

Headley pleaded guilty and co-operated to avoid the death penalty and extradition to India.

More than 160 people were killed by gunmen during the assault.

After initially denying the charges, Hadley eventually pleaded guilty and admitted to scouting potential target locations in Mumbai.

He also confessed to helping plan an aborted plot to behead staff at a Danish newspaper that had published a cartoon many Muslims deemed offensive.

'Unfathomable damage'

Headley had faced life imprisonment but US District Judge Harry Leinenweber said he had taken into account the American's co-operation in the case, even if "the damage that was done was unfathomable".

"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," Judge Leinenweber said during Thursday's verdict.

Headley was born Daood Gilani to a Pakistani father and American mother but changed his name to David Coleman Headley in 2006 "to present himself in India as an American who was neither Muslim nor Pakistani", prosecutors said.

Headley is alleged to have told prosecutors that he had been working with LeT since 2002.

He was arrested by FBI agents in Chicago in October 2009 while trying to board a plane for Philadelphia.

Earlier this month, Canadian-Pakistani businessman Tahawwur Rana was jailed in Chicago for 14 years for providing support to LeT.

Headley had been the government's star witness against Rana, an old friend from their days in a Pakistani military school.

On 17 January, Rana was found guilty of providing material support to LeT and helping to plan an aborted attack on Danish newspaper Jyllands-Posten. He was, however, cleared of playing a role in the Mumbai attacks.

The 60-hour assault on Mumbai began on 26 November 2008. Attacks on the railway station, luxury hotels and a Jewish cultural centre claimed 166 lives. Nine gunmen were also killed.

The only surviving attacker, Pakistani Mohammad Ajmal Amir Qasab, was executed in India last November.