A missile believed to have been launched by an unmanned US drone killed at least seven suspected pro-Taliban fighters in South Waziristan on Wednesday, intelligence officials and Taliban sources said.
The US military does not confirm unmanned drone attacks but its forces and the Central Intelligence Agency (CIA) in Afghanistan are the only agencies that use such aircraft in the region.
The Wall Street Journal newspaper reported on Thursday that Washington was planning further drone attacks in Pakistan.
The drone programme, which the US administration reportedly views as "a success", is under evaluation as part of a review of the US military strategy in Pakistan and Afghanistan.
Intelligence officials from the US and Pakistan are composing a "fresh list of terrorist targets for drone strikes along the Pakistan-Afghanistan border," the Wall Street Journal said citing officials involved.
Adjustments could me made to "change the pace and size of the programme, and make some technical refinements in an effort to hit targets faster".
Reports from Pakistani officials, residents and fighters say around 30 attacks have killed more than 300 people since August 2008.
The Pakistani government has protested to Washington that drone strikes violate its territorial sovereignty, saying that the attacks are counterproductive as the civilian casualties they often inflict have boosted support for fighters in the area.
The US accuses Pakistan of not doing enough to crack down on fighters who cross the border to attack US and Nato troops in Afghanistan.
The New York Times, citing American, Pakistani and other security officials, reported on Thursday that operatives in Pakistan’s military intelligence agency are aiding the Taliban’s campaign in southern Afghanistan.
"The support consists of money, military supplies and strategic planning guidance to Taliban commanders," the newspaper reported.
"There is even evidence that ISI [Directorate for Inter-Services Intelligence] operatives meet regularly with Taliban commanders to discuss whether to intensify or scale back violence before the Afghan elections."
Hundreds of Taliban and al-Qaeda fighters sought refuge in Pakistan's northwest tribal region after the US-led invasion of Afghanistan toppled the Taliban regime in late 2001.