India picked up intelligence in recent months that terrorists were plotting attacks against Mumbai targets, an official said Tuesday, as the government demanded that Islamabad hand over suspected terrorists believed living in the Pakistan.
A list of about 20 people - including India's most-wanted man - was submitted to Pakistan's high commissioner to India on Monday night, India's foreign minister, Pranab Mukherjee said.
India has already demanded Pakistan take "strong action" against those responsible for the attacks, and the US has pressured Islamabad to co-operate in the investigation.
America's chief diplomat, Secretary of State Condoleezza Rice, will visit Indian Wednesday.
The diplomatic wrangling comes as the government faces widespread accusations of security and intelligence failures after suspected Muslim militants carried out a three-day attack across India's financial capital, killing 188 people and injuring more than 300.
The only surviving attacker has told police that he and the other nine gunmen had trained for months in camps in Pakistan operated by the banned Pakistani militant group Lashkar-e-Taiba.
India's foreign intelligence agency received information as recently as September that Pakistan-based terrorists were plotting attacks against Mumbai targets, according to a government intelligence official familiar with the matter.
The information was then relayed to domestic security authorities, the official said.
But it's unclear what, if anything, the government did with the intelligence after that.
The famous Taj Mahal hotel, scene of much of the bloodshed, had tightened its security with metal detectors and other measures in the weeks before the attacks, after being warned of a possible threat.
But the security precautions "could not have stopped what took place," Ratan Tata, chairman of the company that owns the hotel, told CNN.
"They (the gunmen) didn't come through that entrance. They came from somewhere in the back."
Pakistan's foreign minister Shah Mehmood Qureshi on Tuesday said his country had offered investigators to help India probe the Mumbai attacks.
"The government of Pakistan has offered a joint investigation mechanism and we are ready to compose such a team which will help the investigation," he said in a televised statement.
The minister, speaking Urdu, said both governments needed to show "maturity, seriousness and patience" amid rising tensions between the nuclear-armed rivals after suspected Pakistani militants killed 188 people in Mumbai.
However, Pakistan's top diplomat dodged Indian demands to hand over the 20 suspected militants said to be on its soil.
"I have offered this (co-operation) to my Indian counterpart Pranab Mukherjee and to the Indian government in response to their statement. We have sent this reply that Pakistan is ready to extend all kinds of co-operation and assistance," he said.
Earlier, Pakistan's information minister Sherry Rehman said Islamabad would consider India's request and respond after receiving the list.
A day after soldiers finishing removed the last bodies from the hotel, where the standoff finally ended on Saturday morning, wood boards covered its marble latticework and seafront entrance as plain-clothed police searched for evidence.
The building was the last to be cleared, following the five-star Oberoi hotel, a Jewish centre, and other sites struck in this city of 18 million.
Mumbai began returning to normal on Monday as children returned to school, shopkeepers opened their businesses and restaurants began serving again.
Prime Minister Manmohan Singh, who has promised to strengthen maritime and air security and look into creating a new federal investigative agency, met with top security aides to review any government lapses on Tuesday.
Among the prisoners sought by India is Dawood Ibrahim - a powerful gangster, the alleged mastermind of 1993 Mumbai bombings, and India's most-wanted man.
Also included is Masood Azhar, a terror suspect freed from an Indian prison in exchange for the release of hostages aboard an Indian Airlines aircraft hijacked on Christmas Day 1999.
While the cross-border rhetoric between Pakistan and India has increased since the attacks, both countries - by their often-bellicose standards - carefully refrained from making statements that could quickly lead to a buildup of troops along their already militarised frontier.
In India, Pakistan's high commissioner met with foreign ministry officials late Monday and was told that "elements from Pakistan" had carried out the attacks.
The commissioner was told that India "expects that strong action would be taken against those elements," said foreign ministry spokesman Vishnu Prakash.
Pakistan has repeatedly denied any involvement in the attacks.
Pakistani President Asif Ali Zardari said on Monday the gunmen were "non-state actors," and the government has proposed a joint investigation.
With the investigation still under way, and FBI and Scotland Yard teams assisting, more details emerged about the suspects and the attacks.
The sole surviving attacker, Ajmal Qasab, told police his group trained over about six months in camps operated by Lashkar in Pakistan, learning close-combat techniques, hostage-taking, handling of explosives, satellite navigation, and high-seas survival skills, according to two Indian security officials familiar with the investigation.
Lashkar was outlawed in Pakistan under pressure from the US in 2002, a year after Washington and Britain listed it a terrorist group.
Qasab told investigators the militants hijacked an Indian vessel and killed three crew members, keeping the captain alive long enough to guide them into Mumbai, the two security officials said.
The men, ages 18-28, then came ashore in a dinghy at two different Mumbai areas before slipping into the city in two teams, officials said.
The gunmen hired two separate taxis after reaching Mumbai, planting bombs that later exploded in each vehicle, officials said.
Two more unexploded bombs were found outside the Taj Mahal hotel.
The gunmen struck at several sites, including a train station, where they mowed down police and passers-by; the Jewish centre; and the two luxury hotels, representing the city's wealth and tourism, reportedly seeking out Westerners.
Two Australians were among 22 foreign nationals killed in the attacks.
