Updated

Palestinian security officials say clashes have erupted in a densely-packed refugee camp in southern Lebanon, wounding at least four civilians, including a three-year-old boy with a bullet-wound to the head.

Smoke could be seen rising above the Ein el-Hilweh camp on Tuesday and gunfire could be heard from the nearby port city of Sidon.

The Lebanese army, which according to a longstanding agreement is not allowed inside the Palestinian camp, says it has closed a major highway nearby. Schools around the camp are also closed.

The Palestinian officials spoke on condition of anonymity because they were not authorized to brief reporters.

Ein el-Hilweh, split between supporters of the Palestine Liberation Organization and Islamic militant groups, is notorious for its lawlessness. The U.N. says more than 50,000 Palestinian refugees live there.