A frogman is someone who is trained to dive, swim and combat.
"The role of frogmen was confirmed by Headley when the Indian investigators interrogated him in the US last month," an official said.
This is being seen as another clear indication of the Pakistani establishment’s involvement in the planning and execution of the Mumbai terror attack, which claimed 168 lives.
Home Secretary Gopal K Pillai had recently said that the ISI was "literally controlling and coordinating the (Mumbai) attack from beginning to end".
Pakistani-American Headley, currently in American custody, was interrogated by a team of National Investigation Agency.
Officials said that the Indian investigators so far have no plan to interrogate Headley’s accomplice Tahawwur Hussain Rana, a Pakistani origin Canadian citizen, as his involvement in the Mumbai attack conspiracy was limited to providing finance.
"If necessary we may interrogate Rana also, though we have no immediate plan to do so," an official said.
Headley has also told his interrogators that the Pakistani intelligence agency had paid Rs 25 lakh to LeT to purchase a boat which terrorists used to travel from Karachi to the Pakistani maritime boundary, where they hijacked an Indian fishing boat ‘Kuber’ to reach Mumbai.
Headley also identified, through voice sample test, two ISI officers believed to be in constant contact with the terrorists who carried out the 60-hour attack in Mumbai on November 26, 2008.
Officials said Indian investigators have information that ISI chief Lieutenant General Ahmed Shuja Pasha had met one of the handlers of the Mumbai attack, Sajjid Mir, who is currently in a Pakistani jail.
"All this information have been shared by India with Pakistan through the multiple dossiers given to it," the official said.