A day-old truce between army forces and a militant Palestinian faction holed up inside a refugee camp in northern Lebanon was shattered late Thursday as heavy gunfire was reported in the area.

A Lebanese soldier jokingly throws a stone at a colleague during a quiet moment at one of the entrances to the Nahr el Bared refugee camp near the city of Tripoli in Lebanon Friday.
(Ben Curtis/Associated Press)

It was not clear what prompted the exchanges. Until sundown Thursday, only sporadic gunfire had marred the truce.

The clashes have forced many Palestinian refugees and Lebanese living in the Nahr el Bared camp to flee. Thousands are still believed to be caught in the crossfire as the Lebanese government cracks down on Fatah al-Islam, a group believed to have links to al-Qaeda.

A convoy of 11 aid trucks left Amman, Jordan Thursday to deliver 220 tons of food for the thousands of Palestinians trapped in the camp. The Red Cross says it has been having only limited success in gaining access to the camp.

Earlier Thursday, the Lebanese army moved troops around the camp but did not try to advance, apparently giving time for negotiations and for the militants to comply with a government ultimatum to surrender or face a military assault.

Fighting between the Lebanese army and militants erupted Sunday in the country's worst internal violence since the 1975-1990 civil war. It began when police raided an apartment, looking for suspects in a bank robbery in the northern Lebanese city of Tripoli. The militants resisted arrest and gun battles broke out.

The group took up residence late last year in the camp, which the troops are not allowed to enter under a deal between Lebanon's government and Palestinian officials.

Ahmadinejad threatens Israel over Lebanon

In another development, Iranian President Mahmoud Ahmadinejad warned Israel on Thursday that other nations in the region would take action against the Jewish state if it attacked Lebanon in the summer.

A 34-day war erupted last July between Israeli forces and Hezbollah guerrillas ensconced in southern Lebanon after Hezbollah killed three Israeli soldiers and captured two others in a cross-border raid.

"If this year you repeat the same mistake of the last year, the ocean of nations of the region will get angry and will cut the root of the Zionist regime from its stem," Ahmadinejad told a rally in the city of Isfahan.

The Israeli military has been targeting Hamas militants in the Gaza Strip with air strikes over the past week in response to the militant group's repeated rocket attacks on Israeli border towns. Nearly 200 rockets have landed in Israel this week, killing one woman.    

"If you think that by bombing and assassinating Palestinian leaders you are preparing ground for new attacks on Lebanon in the summer, I am telling you that you are seriously wrong," Ahmadinejad said. 

With files from the Associated Press