Upto 95 people were reportedly killed and 200 injured in a single day of clashes between rival tribes in Pakistan's troubled North West Frontier Province, which is already engulfed by steep rise in militancy violence.

The fighting between Khurram and Bangash tribesmen re-erupted on Saturday after a brief lull and a bloody Sunday left a trail of 95 tribesmen killed.

The clashes in the Khurram agency, media reports said, were sparked almost a month ago by the burning of a tribesman's tractor by a rival tribesman.

Reports suggested that the Bangash tribe is being supported by local Taliban militia. Missiles, rockets and other heavy weapons were used by the rival tribesmen during the clashes when they attacked each others' positions.

The fighting began when Bangash tribesman attacked Turi positions, leaving five persons dead and several others injured.

Turis retaliated by forming a lashkar or local militia and raiding Bangash positions in their stronghold of Bagzai. The area comprising about 200 villages fell to the Turi tribe and the lashkar occupied the strategic Esar Ghundai bunker.

Sources were quoted by the influential Dawn newspaper as saying that three suicide attacks were carried out against the Turis by supporters of the Bangash tribe, killing and injuring a large number of people.

A suicide bomber blew himself up in Esar Ghundai and another detonated his explosives in a seminary while one was killed by the lashkar.

The semi-autonomous Kurram Agency has been affected by violent sectarian clashes between Shia and Sunni tribesmen since last year, and recent clashes between the Turi and Bangash tribes have added to problems in the area.

The fresh fighting erupted over the weekend despite a unilateral ceasefire called by the Turi tribe in view of the holy Islamic month of Ramadan.

Thousands of people have been displaced by violence in Kurram Agency and their property ransacked, looted or torched during the fighting. The violence has resulted in the closure of major roads in the area, causing a severe shortage of food and medicines.

In the past, Kurram Agency has witnessed sectarian clashes almost every three to five years, but the violence would die down quickly because of a combination of political and administrative measures and use of force.

The Sunni elders have lost their authority to a band of displaced people of their sect and Taliban militants while the Shia elders are fast losing influence to a violent militant faction called the Mahdi Militia.