At least two people were killed and 20 others were wounded Friday when Lebanese troops opened fire on angry Palestinian refugees trying to march back home to their besieged camp in northern Lebanon, Palestinian officials said.

Thousands of Palestinian refugees had fled the Nahr el-Bared camp where the army has been battling Islamic militants since May 20. Most have been sheltered since in the Beddawi camp, just 3 miles away.

But with the fighting dragging on between the military and the Fatah Islam militants holed up inside Nahr el-Bared, the displaced refugees are now demanding they be allowed to return to their homes.

On Friday, about 2,000 of them staged a protest at the Beddawi camp, after which some angrily tried to march to Nahr el-Bared.

But when they reached an army checkpoint outside the camp, the military told them to disperse and return to Beddawi. As the refugees continued to march, the soldiers opened fire, first in the air and then into the crowd, in an attempt to disperse the marchers.

At least two protesters were killed and 20 others were wounded in the melee, some by gunfire and others in the stampede that followed, the officials said, speaking on condition of anonymity because they were not allowed to give statements to media.

Protests against prolonged fighting at Nahr el-Bared were also held Friday in Palestinian refugee camps in south Lebanon and in Beirut, but no violence was reported at those rallies.

The fighting at Nahr el-Bared has become the worst internal violence since Lebanon's 1975-90 civil war, and is believed to have claimed the lives of more than 160 people, including 84 soldiers, at least 60 militants and more than 20 civilians.

It first began five weeks ago in the northern port city Tripoli, a largely Sunni city. Then, it shifted to the Nahr el-Bared camp, after the Fatah Islam militants barricaded themselves inside it.

Last weekend, it moved back to Tripoli, and on Thursday the military raided a militant hideout in the hills south of the city.

The Al Qaeda-inspired Fatah Islam is believed to consist of mostly foreign Sunni fighters, and Lebanon's Western-backed government has accused the group of trying to launch a rebellion in