Miranshah: Clashes between two Pakistani Taliban factions have left at least 20 dead, security officials and militant sources said on Monday, in a sign of the intense rivalries within the umbrella grouping.

The fighting took place in the tribal regions between supporters of Khan Said Sajna, a senior commander once tipped to lead the group, and those of former leader Hakimullah Mehsud who was killed in a US drone strike last November.

A security official in Islamabad told AFP that at least 15 militants were killed in a overnight clash between the groups along the border of the North and South Waziristan tribal agencies.

Another security official and two militant sources in North Waziristan confirmed the clash.

Fighting broke out once again on Monday, killing a further five militants.

“At least five people including a commander of Hakimullah Mehsud was killed in a rocket attack on a vehicle in South Waziristan,” a local security official said, naming the commander as one “Shadeed Mehsud”.

“The dead bodies were severely burnt in the attack carried out in Shaktoi area and complete identification of the militants was difficult,” he added.

The second attack was confirmed by a militant source.

The reason for the clashes was unclear. But the umbrella Tehreek-e-Taliban Pakistan (TTP) group which was formed in 2007 has long been riven by infighting.

Khan Said Sajna, head of his own faction, was a strong candidate to become TTP chief following Mehsud’s death.

But the movement’s Shura (advisory board) at the last minute elected Mullah Fazlullah, who hails from Swat and is believed to be hiding in Afghanistan.

The Pakistani government began negotiations through intermediaries with the TTP in February to try to end its bloody seven-year insurgency.

The TTP have demanded the release of what they called “non-combatant” prisoners and the establishment of a “peace zone” from which security forces would be barred.