"If the random shelling does not stop... there will be uprisings  in all the camps in Lebanon," Sultan Abul Aynayn, the head of Fatah in the country, told the AFP news agency.

Major Palestinian factions, including the Fatah and Hamas, have distanced themselves from Fatah al-Islam and denounced the fighting, warning that it endangered Palestinian civilians.

Abul Aynayn said hundreds of Palestinians had taken part in the demonstration in Beddawi, home to more than 16,000 refugees.

Palestinian refugees in Lebanon

- 400,000 Palestinians refugees live in Lebanon

- Twelve refugee camps house more than 215,000 Palestinians

- Palestinian refugees make up more than 10 per cent of Lebanon's population

- Ain el-Hilweh is the largest refugee camp with 45,000 residents

Source: Reuters/United Nations/UNRWA

"This is just a small token of what might happen in all the Palestinian camps in Lebanon," he said at the camp on the northern outskirts of Tripoli about 10km south of Nahr al-Bared.

"No Palestinian or Palestinian faction in Lebanon will accept seeing the Palestinian people slaughtered in a collective punishment, as is happening in Nahr al-Bared," he added
  
Many demonstrators shouted they were "ready to be martyrs for Nahr al-Bared" as they burnt tyres in protest.

In Ain el-Helweh, near the southern port city of Sidon, protesters burnt tyres and blocked roads.

Al Jazeera's Mike Hanna visited the Beruj al-Barajni camp on Tuesday where he found anger at Fatah al-Islam for provoking the crisis.

"They are trying to drag the Palestinians into the war," one refugee told him. "They use the word Fatah, because it is related to Palestinians, and Islam because there is a campaign around the world against Islam."

Another said: "We are against what Fatah al-Islam is doing, but at the same time there are civilians being hurt, there are civilians being killed."

Lebanon is home to about 400,000 Palestinian refugees, half of whom live in 12 camps which remain outside the control of the Lebanese government under an arrangement reached four decades ago.