"The army made a breakthrough in the last quarter where the Fatah Al Islam gunmen are entrenched" in Nahr Al Bared, an officer on the scene said.

The soldiers "destroyed some buildings with explosives, uncovering the entrances to underground tunnels and fortifications" still held by the die-hard extremists, he said.

An army spokesman confirmed that there had been progress Thursday.

"This advance is progressing slowly because of the rubble and the booby-trapped terrain," he said.

Meanwhile the military continued to bombard Nahr Al Bared, starting a number of fires in the impoverished shantytown, a witness said.

Sheikh Mohammed Al Hajj, a Muslim cleric who has acted as a mediator in previous bids to end the crisis, said that the army has agreed to let his team enter the camp again to contact Fatah Al Islam.

But a military spokesman would not confirm this, saying only that the army "seeks the unconditional surrender of the gunmen."

More than 200 people, including 136 soldiers, have been killed since the conflict started May 20, in the worst internal violence since the end of Lebanon's 1975-90 civil war.

Most of the camp's 31,000 residents have fled since the battles erupted, but about 60 women and children related to Fatah Al Islam fighters remain inside Nahr Al Bared. The army has accused the Islamists of using them as human shields. Agencies