United Nations chief Antonio Guterres has called for an end to violence in Libya in accordance with a UN-brokered ceasefire agreement. At least 39 people have been killed and over 100 injured in five days of clashes among rival militias in suburbs south of Tripoli.<br />''<br />'' A statement from Secretary-General's office said Mr. Guterres urged all parties to immediately cease hostilities. In a joint statement Britain, France, Italy and the United States have said they warned those who tamper with security in Tripoli or elsewhere in Libya. <br />''<br />''The Libyan capital has been at the center of a battle for influence between armed groups since the fall of dictator Moamer Kadhafi in 2011. <br />