MIRANSHAH  - At least four soldiers were killed and five wounded when a military convoy struck a roadside bomb in North Waziristan on Thursday, security officials said.

The convoy was passing through Spinwam village some 45 kilometres east of Miranshah, the main town of the North Waziristan tribal region, which is a hub of Taliban and Al-Qaeda linked militants on the Afghanistan-Pakistan border.

Officials blamed ‘miscreants’ - a term they often use for Taliban militants -- for the attack.

"Two more soldiers embraced Shahadat (martyrdom). The death toll has now risen to four, the roadside IED was planted by miscreants," a senior security official told AFP, updating his earlier death toll of two.

Five soldiers were wounded in the blast from the improvised explosive device (IED), the official said.

A second security official said one military truck was badly damaged in the attack.

Ansarul Mujahideen, a little known militant group linked to the umbrella Tehreek-e-Taliban Pakistan (TTP), claimed responsibility for the attack.

"It is in retaliation to the drone strike in Hangu," Abu Baseer, a purported spokesman of the group told AFP by telephone, threatening more attacks.

Hangu is in Khyber Pakhtunkhwa, where a US drone struck a religious seminary in November, killing six militants.

The attack, which militant sources said killed the spiritual leader of the ruthless Haqqani militant network along with five others, was unusual in that it was mounted outside Pakistan's lawless tribal areas on the Afghan border.

The TTP and Al-Qaeda-linked militants have led a bloody campaign against the Pakistani state in recent years, carrying out hundreds of attacks on security forces and government targets, concentrated largely in the northwest.