The armies of Cambodia and Thailand have exchanged fire across their border for a fourth day. Artillery and machine gun fire was heard in the disputed area around the 11th Century Preah Vihear temple, which was damaged in earlier fighting. UN Secretary-General Ban Ki-moon said he was deeply concerned by reported armed clashes between Cambodia and Thailand in their border area, and called on both sides to make an effective arrangement to end hostilities and exercise maximum restraint. Cambodian Prime Minister Hun Sen sent a letter to the UN Security Council requesting to convene an urgent meeting to stop Thai invasion into Cambodian territory. At least five people were killed in clashes on Friday and Saturday.