BEIRUT, May 21 (Xinhua) -- A UN body on Monday warned of a unfolding humanitarian crisis at the northern Palestinian refugee camp of Nahr al-Bared where the Lebanese army is locked in battle with militants, which so far has left 57 dead.

    Richard Cook, director of the United Nations Relief Works Agency for Palestine refugees (UNRWA) in Lebanon, described the fighting in and around the camp was "distressing."

    "We are deeply concerned about the developing humanitarian crisis, particularly the danger to civilian lives," he said in a statement.

    As fighting between the Lebanese troops and militants around the Palestinian refugee camp in northern Lebanon entered the second day on Monday, the soldiers tightened their grip around camp and were shelling positions of the Fatah al-Islam faction at the entrances of the camp.

    By noon, 57 people, including 27 soldiers, had been killed in the two day's fighting, rising from last night's toll of 48. Local media said most of the killed on Monday are civilians.

    Some 30,000 displaced Palestinians live at the camp. Under a 38-year-old deal, Lebanese police and soldiers do not enter Palestinian refugee camps.

    But with the military tightening the grip around the camp, the refugees have reported electricity and water cuts.

    Media reports said more than 70 were also wounded in the camp Monday, many of whom were trapped inside the camp and could not get timely medical treatment.

    The fighting started at dawn on Sunday after security forces raided homes in the refugee camp to arrest suspects in a bank robbery happened one day ago, when four masked gunman robbed a bank in the northern town of Amioun and made off with 125,000 U.S. dollars in cash.

    The camp-based Fatah al-Islam militants attacked Lebanese army posts at the refugee camp after the arresting operation.