U.S.-led coalition and Afghan security forces backed by airpower killed about 70 suspected militants in Afghanistan, where violence is running at its highest level since the ouster of the Taliban regime six years ago, authorities said Saturday, accoridng to AP. The surge in militant attacks comes despite the presence of more than 50,000 foreign troops and 110,000 Afghan police and military officers, as well as a multimillion dollar reconstruction effort to rebuild the shattered nation. Late Friday, Afghan security forces backed by U.S.-led troops raided compounds in three villages in the remote Pitigal Valley border region. The coalition said intelligence showed that top militant leaders take refuge in the area as they travel between Pakistan and Afghanistan. Afghanistan has accused Pakistan of failing to do enough to prevent the movement of militants and weapons across the frontier. Pakistan _ which before 2001 had close ties with the Taliban _ denies the charge, saying it has deployed tens of thousands of troops. The troops killed more than 20 insurgents and detained 11 others in the raids, which took place just 6 kilometers (3 miles) from the border. They discovered a bomb-making factory and seized various weapons and communication gear, the statement said. One coalition solider was injured in the raids, it said. Meanwhile, a bomb attached to a bicycle in a commercial district of the northern city of Mazar-e-Sharif wounded nine people, two seriously, said police spokesman Sher Jan Durani. Police were investigating the motive of Saturday's blast. In the central province of Ghazni, where the Taliban last week released 19 South Koreans they had held hostage for six weeks, Afghan police attacked a group of Taliban planning to strike security forces, killing 18 and arresting six others, said provincial police Gen. Ali Shah Ahmadai. «It was a successful operation,» he said. A coalition statement said the raid resulted in the seizure of mortar and artillery rounds, numerous hand grenades, rocket-propelled grenades and other ammunition, it said. It gave no more details. The Taliban abducted 23 South Koreans in Ghazni six weeks ago. They killed two male hostages, released two women last month and freed the final 19 last week after holding unprecedented negotiations with the South Korean government that critics said risked emboldening the insurgents. In the Musa Qala district in southern Helmand province, a combined police and coalition patrol came under attack on Friday from mortars, rocket-propelled grenades and small-arms fire, the coalition said in a statement. In the fight that ensued, almost two dozen insurgents were killed. No Afghans or coalition soldiers were killed, the statement said. Also in Musa Qala, Afghan forces Saturday called in coalition airstrikes after coming under attack, the coalition said. The strikes on the «known enemy positions» killed seven insurgents, the statement said. Militants have been running parts of Musa Qala since a peace deal last year between local elders and Afghan government officials, supported by British troops in the province. The deal effectively turned Musa Qala town and surrounding areas over to Taliban control. It was not possible to independently verify any of the death tolls because travel to the areas is extremely dangerous. Taliban commanders were not available for comment. The Taliban ruled most of Afghanistan from the mid-1990s until 2001, imposing an extreme version of Islam and harboring al-Qaida leaders and thousands of other Muslim militants from around the world. They were ousted by a U.S.-led coalition following the Sept. 11, 2001, attacks in the United States, but are now leading an increasingly bloody campaign against the country's Western-backed government. More than 4,200 people _ most of them insurgents _ have been killed so far this year, according to an Associated Press count.