Pakistan: Militants suffer heavy casualties as fighting rages

Government forces destroyed four insurgent bases and killed 40 fighters Tuesday in a new offensive near Pakistan's famed Khyber Pass, the main route for supplies to U.S. and NATO troops in Afghanistan, authorities said.

The offensive follows a suicide blast in the region last week that killed 19 police officers at a key border crossing.

Tariq Hayat, the top administrator in Khyber, said that in addition to those killed, 43 fighters were arrested. The four destroyed bases belonged to the militant group Lashkar-e-Islam, he said.

Hayat did not indicate whether a sustained operation was planned in the area, where supply convoys are often targeted.

Pakistan is under intense U.S. pressure to crack down on insurgents close to the Afghan border, a lawless region where al-Qaeda leader Osama bin Laden is suspected to be hiding. The Taliban there also helps mount attacks against Western troops across the frontier.

Elsewhere in the northwest Tuesday, the army said 105 Pakistani Taliban fighters had surrendered in the Swat Valley.