Lebanese authorities say Islamic militants holed up in a Palestinian refugee camp must surrender or face military action.

Defense Minister Elias Murr issued the ultimatum Wednesday, adding the army will not negotiate with Fatah al-Islam militants.

Relief workers say as many as half the 30-thousand residents of the Nahr al-Bared camp have fled since late Tuesday, heading to the nearby Lebanese city of Tripoli and another Palestinian refugee camp Beddawi.

Escaping residents say bodies were lying in the streets or under the rubble of buildings in Nahr al-Bared. About 75 people -- soldiers, militants and civilians -- have been killed since the fighting began Sunday.

Meanwhile, police say five people were wounded in an explosion late Wednesday in the Druze town of Aley, east of Beirut. Officials said the blast was caused by a bomb.

Two explosions this week in different neighborhoods in Beirut have killed a woman and wounded several people.

France says the country's new foreign minister, Bernard Kouchner, will travel to Lebanon on Thursday for talks with Lebanese Prime Minister Fuad Siniora and Parliament Speaker Nabih Berri, among others.

The battles on the outskirts of Tripoli are said to be the worst internal fighting since Lebanon's 15-year civil war ended in 1990.