By Nazih Siddiq NAHR AL-BARED, Lebanon, June 1 (Reuters) - Heavy fighting erupted on Friday between Lebanese troops and al Qaeda-inspired militants entrenched in a Palestinian refugee camp in northern Lebanon, witnesses said. The Lebanese army has been battling Fatah al-Islam militants at the Nahr al-Bared camp intermittently for almost two weeks. Artillery shelling and machinegun fire rocked the camp from early morning in the latest clashes, which were fiercest near its northern and southern entrances. Smoke billowed from breeze block buildings inside the camp, television footage showed. The violence at Nahr al-Bared is Lebanon's worst internal fighting since the 1975-1990 civil war. So far it has cost the lives of at least 83 people -- 34 soldiers, 29 militants and 20 civilians. A Lebanese soldier was killed and three others were wounded in fighting on Thursday. The government is demanding that the militants surrender and the authorities have already charged 20 captured members of the group with terrorism. The charges carry the death penalty. A 1969 Arab agreement prevents the army from entering Lebanon's 12 Palestinian camps, home to 400,000 refugees. The Lebanese government has given Palestinian leaders in Lebanon a chance to find a way out of the two-week stand-off because it fears the fighting could spark violence in other refugee camps. Abbas Zaki, the Palestine Liberation Organisation (PLO) representative for Lebanon, urged the Fatah al-Islam militants to give themselves in. More than 25,000 of the Nahr al-Bared's 40,000 Palestinians have fled to the nearby Beddawi camp, where humanitarian organisations have been carrying out relief work. Members of Lebanon's anti-Syrian cabinet have described Fatah al-Islam as a tool of Syrian intelligence, though Damascus denies any links to the group and says its leader, Shaker al-Abssi, is on Syria's wanted list. Abssi has said he follows al Qaeda's ideology, but has no direct links to Osama bin Laden's network. Many of his estimated 300 gunmen are believed to have fought in Iraq. Lebanese authorities say Fatah al-Islam includes Arabs from Saudi Arabia, Algeria, Tunisia, Syria and Lebanon.
