PESHAWAR, Pakistan (Reuters) - A U.S. drone strike killed seven people in Pakistan's North Waziristan region on Wednesday, security officials said, the first such attack since a May 11 general election in which the use of the unmanned aircraft was a major issue. U.S. President Barack Obama recently indicated he was scaling back the drone strike programme, winning cautious approval from Pakistan, a key ally in the U.S. fight on militancy. A Pakistani Foreign Ministry official condemned all such strikes. "Any drone strike is against the territorial integrity and sovereignty of Pakistan and we condemn it," the official, who declined to be identified, told Reuters. Pakistani security officials and Pashtun tribesmen in the northwestern region said the drone fired two missiles that struck a mud-built house at Chashma village, 3 km (2 miles) east of Miranshah, the region's administrative town. They said seven people were killed and four wounded. It was not immediately clear if the victims were the intended targets. "Tribesmen started rescue work an hour after the attack and recovered seven bodies," said resident Bashir Dawar. "The bodies were badly damaged and beyond recognition." North Waziristan is on the Afghan border and has long been a stronghold of militants including Afghan Taliban and their al Qaeda and Pakistani Taliban allies. Prime Minister-elect Nawaz Sharif said this month that drone strikes were a "challenge" to Pakistan's sovereignty. "We will sit with our American friends and talk to them about this issue," he said. Obama's announcement of scaling back drone strikes was widely welcomed by the people of North Waziristan, where drones armed with missiles have carried out the most strikes against militants over the past seven years, sometimes with heavy civilian casualties. The strike also coincided with the first session of the newly elected provincial assembly of Khyber Pakhtunkhwa, the former Northwest Frontier Province. Former cricketer Imran Khan's Pakistan Tehrik-e-Insaf party won most seats in the assembly and has been very critical of drone strikes in the region. Pakistan's Foreign Ministry said last week it appreciated Obama's acknowledgement that force alone did not work, adding that the root causes of terrorism had to be addressed. "On the use of drone strikes, the government of Pakistan has consistently maintained that (they) are counter-productive, entail loss of innocent civilian lives, have human rights and humanitarian implications and violate the principles of national sovereignty, territorial integrity and international law," it said.