LANDIKOTAL, Pakistan (Reuters) -- Pakistani soldiers killed 18 militants today in a campaign to break a network orchestrating attacks on Western forces' supplies to Afghanistan and carrying out bombings, a security official said.
Any heavy casualties inflicted on militants in the Khyber region could ease concerns in Washington, which wants Pakistan to root out fighters along the border, seen as a global hub for militants, to help it defeat the Taliban in Afghanistan.
Militants have been trying to choke off the supplies with attacks, forcing the United States and other countries with forces in landlocked Afghanistan to look for alternative routes.
"We have secured one of their strongholds and recovered a large cache of arms and ammunition. In the fighting, 18 militants were killed while six were arrested," said Frontier Corps paramilitary force spokesman Major Fazal-ur-Rehman said.
Political tensions in Pakistan could distract the government from its crackdown against militants behind recent bomb attacks that have killed hundreds.
Pakistan's government published on November 21 a list of people, including four cabinet ministers, who could face prosecution on corruption charges after a controversial amnesty lapses this week.
Embattled President Ali Asif Zardari, also on the list, cannot be prosecuted because of presidential immunity.
However, the politically charged cases involving about 8,000 people, many from his party, could weaken him further and spark a new political crisis.
The U.S. military sends a large proportion of its supplies for the Afghan war through or over its regional ally Pakistan, including fuel for its troops.
Pakistani security forces went on the offensive in the Khyber region in September, forcing militants to forge a pact with the Pakistani Taliban in a bid to put up tough resistance.
Apart from the attacks on supply routes, militants have also been involved in a recent spate of deadly suicide bombings in Peshawar, capital of Northwest Frontier Province, security officials say.
Pakistani troops face pressure on several fronts.
The army went on the offensive in the South Waziristan region on the Afghan border on October 17, aiming to root out militants who stepped up their war against security forces in 2007.
According to the military, about 600 militants have been killed in the South Waziristan assault, while 70 soldiers have been killed.
There has been no independent verification as journalists are not allowed there except on occasional military-escorted trips.