Peshawar, Pakistan ? For the second time in two weeks, a rocket missed U.S. Special Forces hunting Taliban and al-Qaida fighters in Pakistan’s frontier tribal belt, a local official said Saturday.

The target was a vocational school in Miran Shah where about seven Americans are thought to bunk while working with Pakistani troops in the semiautonomous region along the Afghan border.

U.S. officials haven’t confirmed their presence at the building.

In Afghanistan, meanwhile, some 600 Afghan refugees who were thwarted in attempts to reach Australia before the U.S.-led war began returning home Saturday. At the same time, about 200 Pakistani prisoners captured while fighting alongside the Taliban were sent back to their country.

Speaking on condition of anonymity, the official in Miran Shah said two rocket launchers had been hooked up with timers in woods less than a half mile from the school and were aimed at the building.

The first rocket fired about 10:25 p.m. Friday and hit a sports complex 150 to 200 yards from the school, causing little damage and no injuries, he said. The second was set to fire at 2:25 a.m. Saturday, but it was found and defused by authorities, he said.

It was not known who was behind the attack.

The arrival of U.S. Special Forces in the frontier area has provoked protests from the fiercely independent tribesmen, whose region generally has been off limits even to the Pakistani army. The area has been a stronghold of support for Osama bin Laden.

Pakistan says the Americans are providing only communications and intelligence assistance, but tribesmen say they have seen American soldiers with Pakistani troops on raids.