Pakistan has agreed to a 48-hour timetable set by India and the US to formulate a plan to act against Lashker-e-Toiba (LeT) and to arrest at least three Pakistanis who Indian authorities say are linked to the Mumbai terrorist assaults, the Washington Post reported citing a high-ranking Pakistani official.
The official, who spoke on the condition of anonymity because of diplomatic sensitivities, said India had also asked Pakistan to arrest and hand over LeT commander Zaki ur-Rehman Lakhwi and the former director of Pakistan's spy agency Inter-Services Intelligence (ISI), Hamid Gul, in connection with the investigation, the Post said Saturday.
Pakistani President Asif Ali Zardari, who has expressed his country's solidarity with India, is expected to review plans by his nation's top military and intelligence officials and follow through on India's demands, the official was quoted as saying.
"The next 48 hours are critical," the Pakistani official added.
US Secretary of State Condoleezza Rice, the daily said, had urged Pakistan to hand over Yusuf Muzammil, an LeT leader whom Indian and US investigators have identified as the mastermind behind the attacks, and other suspects.
The Post cited an unnamed high-level source in the Indian government as saying India had "clear and incontrovertible proof" that the Pakistan-based LeT planned the attacks and that the group's leaders were trained and supported by ISI.
"We have the names of the handlers. And we know that there is a close relationship between the Lashker and the ISI," the source told the Post.
US intelligence officials, however, were more cautious in their interpretation of the evidence, the US daily said.
Although US analysts acknowledged historical ties between Lashkar and ISI as well as more recent contacts between militants and Pakistani intelligence officers, they said they were not convinced that Pakistan supported the attacks in any significant way.
"Even if there were contacts between ISI and LeT, it's not the same as saying there was ISI support," it quoted an unnamed US counter-terrorism official as saying.
The official, the Post said, would not dismiss the possibility that further evidence would reveal active ISI involvement but said: "The evidence we've seen so far does not get you there."
Indian officials have said the sole surviving gunman in the attacks, who goes by the alias Muhammad Ajmal Kasab, 21, mentioned Lakhwi during police questioning. Police had earlier identified the gunman as Ajmal Amir Kasab.
The Wall Street Journal said Western intelligence officials have been quietly mediating between India and Pakistan. The CIA "is playing a huge role in this and trying to work behind the scenes and get past the emotion", it said citing a former senior intelligence official.
Referring to ISI, the official said, "The ISI and the Pakistani military do not ever want to kowtow to the Indians." Still, the official said, "They're working on some sort of scenario" where people Indian authorities are seeking would be detained and questioned.
Another Western official cited by the Journal said Pakistani President Asif Ali Zardari would like to use the attacks as "an opportunity to get rid of some bad apples".
However, the official said, it would be difficult for him to marshal support from the ISI or military for rounding up any alleged culprits.
US and other Western officials have backed India's account of the roots of the Mumbai attacks, to a point. "When it comes to the connections with Lashker, that's absolutely true," a counter-terrorism official was quoted as saying. But Kasab's statements will take time to verify, he added.
Indian police have a sample of Kasab's DNA that they plan to provide to the FBI, which would check whether he is from the family he claims as his own in Faridkot village, the Journal said. The bureau would need to compare it with the DNA of any family member.
The New York Times also cited a senior American counter-terrorism official as saying it was highly likely that local accomplices were involved.
"They couldn't have gotten to the places they did without local help," the unnamed official cited by the Times said. "They just moved too quickly. They had to have had more assistance on the ground."