A suicide bomb attack on a Pakistani checkpoint in the lawless region of North Waziristan killed at least three soldiers and wounded 32 people, intelligence and militant sources said.

Intelligence sources on Wednesday told Reuters that a truck laden with explosives rammed into a checkpoint in North Waziristan, a stronghold for al-Qaeda linked Taliban fighters, killing at least three military personnel.

Pakistan is fighting an increasingly active insurgency mounted by Taliban fighters, adding to a list of concerns for Prime Minister Nawaz Sharif at a time when the government is trying to engage armed groups in peace talks.

A Taliban source told Reuters the attack was in revenge for continued US drone strikes in the region against fighters holed up the mountainous areas on Pakistan's border with Afghanistan.

The Pakistani army imposed a curfew in the area after the attack, said intelligence sources.

Taliban attacks have been on the rise in Pakistan since Sharif came to power in a May election.

The insurgency elected a new leader, Mullah Fazlullah, last month after its previous chief was killed in a US drone strike.

Fazlullah has rejected talks with the government and has promised to step up attacks against the government.

Source: Reuters