Scores of armed militants crossed the border from Afghanistan on Thursday and stormed a village in Pakistan\'s tribal belt, killing five civilians, Pakistani officials said. Afghan officials denied any cross-border attack and accused Pakistani troops of killing six people in a rocket attack on Wednesday. It was the third such attack reportedly carried out by hundreds of fighters into northwest Pakistan this month. The border is porous and tensions between Afghans and Pakistanis are high over Islamist militants in both countries. Pakistani officials said the militants attacked Mamoond village in Bajaur district, which borders the Afghan province of Kunar. \"Some 250-300 militants targeted civilians in Mamoond. At least five civilians, including two women were killed,\" local government official Fazle Akbar told AFP. Akbar said three women were wounded in the attack, which took place about 65 kilometres (40 miles) northwest of Khar, the main town in Bajaur. Muhammad Ilyas Khan, a government official in Mamoond, and security officials in the northwest confirmed the attack and casualties. \"About 300 militants came from Afghanistan and attacked villagers,\" Khan said. \"Fighting is still going on. Tribesmen from the local lashkar (militia) have joined paramilitary forces and army artillery is pounding shells.\" Kunar police chief Mohammad Ewaz Nazir told AFP that Pakistani troops had been shelling the Shigal district of the province for a month. \"Four children and two men were killed in one of their rocket attacks on the Chugam area of Shigal district yesterday.\" \"There hasn\'t been any attack from Afghan soil on Pakistani territory today or yesterday,\" he added. But Pakistani officials rubbished the Afghan denial. \"We cannot say why Afghans are denying the attack, but we are certain that the militants came from across the border,\" a Pakistani security official said. Pakistani troops have carried out a series of operations against the Taliban and other Islamist militants in Bajaur since August 2008. The military has repeatedly claimed to have eliminated the militant threat. Bajaur is one of seven districts in Pakistan\'s semi-autonomous tribal belt that the United States considers the global headquarters of Al-Qaeda. On June 1 and June 3, hundreds of militants besieged an area in Pakistan\'s northwestern district of Upper Dir on the Afghan border, sparking prolonged fighting that killed at least 34 people. At the time, Pakistan conveyed \"strong concern\" to the Afghan ambassador to Islamabad, calling for \"stern action\" by Afghan and US-led NATO troops to crack down on militants in eastern Afghanistan.