A suicide bomber blew himself up at a Pakistani security post in the Swat valley Saturday killing five soldiers, while eight militants were killed in a clash, in the most serious violence in the area for weeks. The military went on the offensive in the region northwest of the capital in late April and has killed or driven out many Taleban militants in what has been widely seen as a successful operation. The army push has allayed fears among allies, in particular the United States and other countries with troops in neighbouring Afghanistan, that nuclear-armed Pakistan was failing to get to grips with spreading Islamist violence. The car-bomb attack in Khawazakhela, about 14 km north of Swat's main town of Mingora, raised concern that the Taleban could make a comeback, especially as no top insurgent leaders in the former tourist valley were killed or captured. “The bomber rammed his explosive-laden vehicle into the post,” said a senior military official in the region who declined to be identified. Five men were killed and four were wounded. The attack came a day after hundreds of people, including many women, attended a music and dance show to celebrate Independence Day in the valley, where the Taleban had banned music and girls' education. “We celebrated Aug. 14 with great enthusiasm and it appeared as if it was all over,” Mingora market vendor Akbar Hussain said of the violence. “Today has again brought fear that the Taleban could return.” In a separate incident, eight militants were killed in a clash that erupted as soldiers searched another area, the military said. Pakistan's efforts to suppress militants on its side of the border are vital for a US-led bid to stabilize Afghanistan, where Taleban have threatened to disrupt an Aug. 20 presidential election. US envoy to Afghanistan and Pakistan, Richard Holbrooke, was due in Pakistan later Saturday. The offensive in Swat, 120 km from Islamabad, forced nearly two million people from their homes but many have been returning in recent weeks since the army said most militants had been cleared from the valley. The military said it killed more than 1,800 Taleban in the offensive, but there has been no independent verification of that estimate. The Taleban denied suffering such heavy casualties and have vowed to fight in. In late July, the Taleban issued a recorded message from their leader in Swat, Fazlullah, who said his struggle would continue until Shariah was enforced in the valley. Although Swat is not on the Afghan border, there were fears it was turning into a bastion for fighters intent on bringing down governments in Pakistan, Afghanistan and beyond. The military has also been attacking Taleban in several regions on the Afghan border including South Waziristan, a known haven for Taleban and Al-Qaeda. In a major blow to the militants, Baitullah Mehsud, the leader of Pakistani Taleban and an Al-Qaeda cohort, was believed to have been killed in a missile strike by a CIA-operated drone in South Waziristan last week