There was mounting evidence that a Kashmiri-based Pakistani militant group, most likely Lashkar-e-Taiba, was responsible for the deadly attacks in Mumbai, according to The New York Times website report.
Citing unnamed intelligence and counterterrorism officials, the newspaper said that US intelligence agencies so far had reached no firm conclusion about who was responsible for the attacks.
But they said that evidence gathered in the past two days pointed to a role for Lashkar-e-Taiba or possibly another group based in Kashmir, Jaish-e-Muhammad, according to the report.
The report came as Indian commandos were locked in heavy fighting inside Mumbai's Taj Mahal Hotel Saturday as they battled to end two-day-old assault by Pakistan-linked militants which has left up to 195 dead, including foreigners.
The paper said the officials declined to discuss specific intelligence. But it pointed out that in the past, US and Indian intelligence services have used communications intercepts to tie Kashmiri militants to terrorist strikes.
According to one Indian intelligence official, during the siege the militants have been using non-Indian cellphones and receiving calls from outside the country, The Times said.
This evidence has led Indian officials to speak publicly about the militants' external ties, the report said.
Lashkar-e-Taiba has denied any responsibility for the terrorist strikes.
US intelligence agencies have said that the group has received some training and logistical support in the past from Pakistan's powerful spy service, the Directorate for Inter-Services Intelligence, The Times noted.
US and Indian officials are investigating the possibility that the attackers arrived off the coast of Mumbai in a large ship and then boarded smaller boats before initiating their attack, the paper said.
A US counterterrorism official said there was strong evidence that Lashkar-e-Taiba had a "maritime capability" and would have been able to mount the sophisticated operation in Mumbai.
