ISLAMABAD: Taliban insurgents had planned to use five Americans, now detained in Pakistan, who had contacted the militants via the Internet, to carry out attacks in the US-allied country, a police official said on Saturday.

"We believe that they were supposed to be used inside Pakistan," Anwar said by telephone. "In their last e-mail to the Taliban, we found they mentioned the Chashma Nuclear Plant and that's why they were going to Mianwali (district)."

Washington is pressuring Pakistan to root out militants in lawless tribal areas who cross the border to attack Western forces in Afghanistan. But it is a sensitive issue.

Pilotless US drone aircraft attacks on suspected militants on Pakistani soil have already infuriated many Pakistanis.

The possibility of militants attempting to attack Pakistan's nuclear weapons alarms Western powers, although analysts say it is highly unlikely.

Reuters