At least four missiles fired by two suspected US drone aircraft hit a house in Pakistan's tribal region of North Waziristan on the Afghan border on Friday, Pakistani intelligence officials say.
At least 25 people were killed in the drone strike, which targeted what one Pakistani official termed a "militant guesthouse" in Hasan Khel, near the region's main town of Miranshah, Al Jazeera's Kamal Hyder in Islamabad reported.
Several people were also wounded in the attack, which took place at around 4:30 am (2030 GMT), an official said, adding that the toll could be higher.
Reports indicate that at least seven women and children were among the dead, Hyder said.
Border clash kills at least 10
Meanwhile, in a separate development, at least 10 Pakistani security forces personnel were killed when hundreds of fighters crossed the border with Afghanistan into Pakistan at Lower Dir early Thursday morning, security forces said on Friday.
The influx resulted in a major clash, Hyder reported, and the security forces called in helicopter gunships and fighter-bomber aircraft for air support.
An official said that the dead included Frontier Corps soldiers and police officials.
The fighters entered Pakistan from the Afghan border province of Kunar, and the clash took place in the Khankai area of Lower Dir.
Pakistan to get 'mini-drones'
On Friday, a US military official told the Reuters news agency that Pakistan would be getting 85 small "Raven" remotely operated surveillance aircraft.
The official, speaking on condition of anonymity, refused to disclose any further details about the non-lethal, short-range aircraft, which are manufactured by US-based AeroVironment.
Friday morning's drone strike came two days after a visit by Admiral Mike Mullen, the top US military official, to Islamabad in which he expressed concern over continuing links between Pakistan's main intelligence agency, the ISI, and armed groups attacking US-led forces across the border in Afghanistan.
North Waziristan is a known sanctuary for al Qaeda and Taliban fighters near the Afghan border.
The United States has been using drone attacks to target al Qaeda-linked groups over the past few years in Pakistan's lawless tribal areas, a source of concern for the Pakistan government, which says civilian casualties stoke public anger and bolster support for the Taliban.
Pakistan has long asked for access to drone technology, and the provision of Raven drones appears to be a US concession towards that demand.