Pak troops pressing an anti-Taliban offensive into a second month in a lawless tribal district near the Afghan border killed at least eight militants on Friday, officials said. Clashes broke out during a military search operation in Goain village, about 25 kilometres (15 miles) west of Kalaya, the main town in Orakzai district, local administration official Fazle Qadir told AFP. Although senior military officials confirmed Friday's fighting and death toll, it is impossible to confirm casualty statistics independently in what is a closed military zone inaccessible to aid workers and journalists. "At least eight militants were killed during a search operation and four of the wounded militants were arrested," the local official said. Two soldiers were also injured in the fighting, Qadir added. Security forces launched the Orakzai offensive on March 24 in a bid to flush out Taliban fighters who escaped a major assault on South Waziristan last year. Washington says Pakistan's tribal belt is a stronghold for Al-Qaeda-linked militants plotting attacks on US-led troops who are fighting a nearly nine-year Taliban insurgency in Afghanistan. Suicide and bomb attacks have killed nearly 3,300 people since July 2007 across nuclear-armed Pakistan, and last year killed more civilians than in Afghanistan. Taliban militants on Friday blew up a state-run girls' school in Sadiqabad village in Bajaur, another of Pakistan's seven tribal districts where militants have destroyed 89 schools, a local administration official told AFP. "Dozens of militants attacked the school and after tying up its security guard they planted explosives and blew up the school," said Adalat Khan. The Pentagon says the United States will soon transfer 600 million dollars to reimburse Pakistan for military operations against militants. The United States has imposed stricter rules on approving reimbursements, creating a backlog and straining US-Pakistan relations.