Militants attacked an army checkpoint in Pakistan's restive north-west on Saturday, leaving at least 35 people dead including 13 members of the country's security forces.
The Pakistan Taliban claimed responsibility for the early morning raid on the army post in Serai Naurang town in Khyber Pakhtunkhwa province.
They said the attack was in response to a US drone strike in neighbouring North Waziristan last month in which two commanders were killed.
The Pakistani military and pro-government militias have since 2009 regained territory from the Pakistan Taliban, who once controlled land a few hours' drive from the capital of Islamabad.
Security sources said at least 12 militants were killed during the firefight, two of whom were wearing suicide belts.
"Cross-firing between militants and security officials continued for four hours," one source said.
The militants also attacked a house next to the camp with rockets, killing 10 members of one family – including three women and three children - sources said.
"Pakistan has been co-operating with the US in its drone strikes that killed our two senior commanders, Faisal Khan and Toofani, and the attack on military camp was the revenge of their killing," the Taliban spokesman said.