No early Pakistan action seen on Lashkar-e-Taiba

That is a problem for India, which believes LeT not only runs its own sophisticated operations like the 2008 attack on Mumbai but is now encouraging disaffected Indian Muslims in the "Indian Mujahideen" to launch small-scale bomb attacks in Indian cities.

Security officials in Pakistan say the country needs to focus first on defeating Pakistani Taliban fighters in its tribal areas on the Afghan border rather than opening up a new front in its heartland Punjab province where Lashkar-e-Taiba is based.

"If you are so up to your neck in the tribal areas, would you like to open another front?" asked one security official.

Unlike other militant groups, LeT has been careful to avoid attacks within Pakistan itself, focusing on India and Indian Kashmir, and as a result has been left largely alone.

"LeT continues to operate almost with impunity in Pakistan," said Rifaat Hussain, who heads the Department of Defence and Strategic Studies at Quaid-i-Azam University in Islamabad.

LeT -- once nurtured by the Inter-Services Intelligence (ISI) agency to fight India in Kashmir -- is estimated to have between 2,000-3,000 gunmen and another 20,000 followers, many trained to fight and who could be mobilised against a crackdown.

The group could ultimately become a major risk for the West -- LeT's charitable wing has wide support and funding from the Pakistani diaspora -- and even threaten Pakistan itself if it decided to try to impose its Islamist views across the country.

Yet Pakistani security officials argue success in its battle against militants depends on its ability to isolate the enemy.

"Do not do anything where all the threat comes together," said one security official. "If we open a front against LeT in central Punjab what would happen? What political support would be there? What is your capability? If you do it, would you overcome the militants or would the militants take over?"

Instead, as with other Punjab-based militant organisations, Pakistan prefers to monitor their activities closely rather than take action which could drive them further underground and create splinter groups which could prove even more dangerous.

"We know who they are, and we try to keep an eye on them," said another security official. "There is no official support."

"Karachi project"

Others, however, say its suits Pakistan to retain an organisation which could be used against India in the event of war, or, some say, to repay in kind what it sees as Indian support for separatists in its Baluchistan province.