New Delhi - An American convicted of plotting the 2008 attacks in Mumbai turned prosecution witness on Thursday after an Indian court granted him a pardon in the case, news reports said.
David Coleman Headley, a US citizen of Pakistani descent, made a deposition before a Mumbai court via video link.
He is serving a 35 years in a US prison after being convicted by a Chicago court in 2013 for helping plan the Mumbai attacks and conspiring to attack a Danish newspaper.
In the hearing on Thursday, Headley admitted to his involvement in the attacks and offered to turn State witness if pardoned by court, the online edition of the Times of India reported.
The court agreed to Headley's plea and asked him to disclose all the information he had revealed to the US court, the report said.
Headley testified in the Mumbai court in accordance with his agreement with the US government that he would participate in foreign judicial proceedings.
Indian police want to question Headley about the alleged involvement of Pakistani army and intelligence officials in the attacks left 166 people dead in the Indian metropolis.
Headley has confessed to being a member of Lashkar-e-Taiba, the Pakistani militant group behind the attacks. He went on scouting trips to Mumbai, making videos of buildings that were targeted in the three-day siege.
Headley, who was earlier questioned by Indian federal investigators, said three senior Pakistan army officers played a key role in the attacks, media reports said. Pakistan has repeatedly denied involvement.
Seven men, including Lashkar operations commander Zaki-ur Rehman Lakhvi are currently undergoing trial in Pakistan.
In 2012, India executed the only surviving gunman, Ajmal Kasab, who was given the death sentence by the Indian courts.