Dozens of insurgents in eastern Afghanistan were killed in battle after more than 100 of them attacked a government center Sunday near the border with Pakistan, an official said. American troops and aircraft assisted Afghan forces during the battle in Spera district of eastern Khost province, said provincial governor Arsallah Jamal. The militants attacked the district center from four directions before being pushed back, Jamal said. More than 50 militants died, while the rest fled into Pakistan, he said. Two policemen died and four were wounded. Separately, several militants were killed and four were detained during an operation in neighboring Paktia province on Saturday, the US-led coalition said. The troops were searching compounds when a group of insurgents fired on them from a fortified position, the statement said. "Coalition forces responded with small-arms fire, killing the militants," it said. Afghanistan faces intensifying militancy nearly seven years after a US-led invasion ousted the hard-line Islamic Taliban movement from power. The number of militant attacks in eastern Afghanistan has increased by 40 percent over the same period last year. Afghan and Western officials say Pakistan has not done enough to crack down on militant hideouts on its side of the border, a charge Pakistan rebuffs. More than 2,700 people - most of them militants - have died in insurgency-related violence this year, according to an Associated Press tally of official figures.