Indian newspapers said on Friday the government had proof that Pakistan's military spy agency was involved in the Mumbai attacks,
including evidence supplied by the US Federal Bureau of Investigation.
"The Inter-Services Intelligence (ISI) connection was clear and evident," the Times of India quoted Indian intelligence sources as saying. The ISI is Pakistan's main spy agency.
The Hindu newspaper said investigations into the Mumbai attack had led to the names of handlers and trainers of the Islamist gunmen and the locations where the training was held. These were believed to be military or ISI men.
At least 171 people were killed in the attacks last week in Mumbai. Nine of the attackers were killed while one is being interrogated.
The detained man told investigators he had attended four training camps in Pakistan over the past 18 months, Mail Today newspaper said.
He has said he is a member of Lashkar-e-Taiba, a Pakistan-based group blamed for previous attacks in India.
The attacks have increased tensions between India and Pakistan. New Delhi says militants based in Pakistan were involved in the attacks, and has demanded that Islamabad hand over 20 of its most wanted fugitives.
The prime suspect for the Mumbai attacks is Lashkar-e-Taiba, an Islamist group fighting Indian rule in disputed Kashmir, and which analysts say has had ties with Pakistani intelligence in the past.