US fears Pak N-weapons might fall into hands of terrorists

"It's a country with an awful lot of terrorists on that border," Admiral Mike Mullen, Chairman of the US Joint Chiefs of Staff, told reporters at a joint Pentagon news conference with Defence Secretary Robert Gates.

"I fear in the future, it's the proliferation of that technology, and it's the opportunity and the potential that it could fall into the hands of terrorists, many of whom are alive and well and seek that in that region. And that's of great interest, I think, to our country and certainly to the rest of the world," Mullen said in response to a question.

Gates argued the US strategy against terrorism is succeeding and Pakistan is playing a contributory role to that.

"It is important to remember that they have 140,000 troops on that border, that at a minimum are stirring things up. They basically cleared South Waziristan and Swat. But even their presence and manoeuvring and so on creates uncertainty," he noted.

Gates said that there is some indication that al-Qaeda is worried because of the way the US went after bin Laden, their suspicion is that the Pakistanis may have been involved in it and are worried that the Pakistanis may betray them, as well.

US President Barack Obama has said he was confident about the security of Pakistan's nuclear arsenal although he was "gravely concerned" about the situation there.

There is a growing concern among US officials that militants might try to snatch a nuclear weapon or infiltrate sympathisers into atomic facilities.