A senior Pakistan Taleban commander is believed to have been killed in a United States drone strike, the first since President Barack Obama announced tighter regulations on their use.
Two missiles were reported to have been fired from an unmanned drone, hitting a house in a village near Miran Shah in North Waziristan.
The operation will further complicate the debate over the use of drones, and will present an immediate challenge for Pakistan's Prime Minister-elect, Nawaz Sharif, whose party campaigned against the programme in elections this month.
Pakistani intelligence officials told Reuters that among up to seven people killed was Wali-ur-Rehman, considered number two in the Pakistan Taleban.
However, there was no immediate independent verification. The Taleban denied that he was dead.
US drone strikes which usually target al-Qaeda and Taleban fighters involved in attacks on Western troops in Afghanistan, are deeply controversial in Pakistan. Analysts said the fact that the Americans targeted the Pakistan Taleban, which has largely attacked targets inside the country, could suggest Pakistani military co-operation.
While there is concern about the number of civilians killed in the strikes, there is equal anger that the drones represent an affront to Pakistan's sovereignty. During his election campaign, Sharif, who will be sworn in next week, said he opposed their use and would withdraw from the Americans' so-called war on terror.
"Drones indeed are challenging our sovereignty. Of course, we have taken this matter up very seriously," he told reporters shortly after his victory.
The party of Imran Khan, which is set to lead a coalition government in northwest Khyber Pakhtunkhwa province, also strongly opposes drones.
The strike was the first since Obama delivered a speech last week in which he said tighter regulations would be imposed on the use of drones in places such as Pakistan and Yemen.
If it is confirmed that the deputy of Taleban commander Hakimullah Mehsud, or another senior Taleban figure was killed, it will strengthen the hand of those who support the drone campaign.