Plumes of smoke were seen rising from the Nahr al-Bared camp, but there were no immediate reports of casualties.
Lebanese troops have surrounded the camp, and are demanding the surrender of Fatah al-Islam militants entrenched there.
Lebanese security officials say the members of Fatah al-Islam include jihadists who are veterans of the war in Iraq. The Lebanese Army has called for international support to combat the militants.
The renewed unrest in northern Lebanon comes as the UN Security Council moved to help resolve an unsettled issue in Lebanese politics by establishing an international tribunal to try suspects in the murder of Lebanese former Prime Minister Rafiq Hariri. Hariri and 22 other people died in a massive bomb blast in February 2005, widely blamed on Syria.
(AP, Reuters, AFP)
The Middle East Crisis
CLASH OF ARMS: Since mid-July, Israel has been battling Hizballah guerrillas in southern Lebanon and carrying out punishing air strikes throughout the country. International efforts to broker a cease-fire have met with one obstacle after another, as civilian casualties mount and a humanitarian crisis unfolds. Since Hizballah is closely supported by Syria and Iran, the conflict threatens constantly to develop into a regional conflagration.... (more)