UNITED NATIONS - At least 150 people, among them Pakistanis, have drowned and scores of others are missing after a boat leaving Libya capsized off the Tunisian coast on Wednesday, the UN refugee agency reported today. The overcrowded boat, which set sail on Saturday from Tripoli, and was headed for Lampedusa in Italy, carried an estimated 850 people, mostly migrants from West Africa, Pakistan and Bangladesh. Some survivors told the UN High Commissioner for Refugees (UNHCR) in Tunisia that the boat was manned by people with little or no maritime experience, according to a UN news release. Soon after it departed Tripoli, the boat ran into difficulties and by the third day the passengers ran out of food and water. The boat eventually ran aground on Wednesday near the Kerkennah islands, some 300 kilometres north-west of Tripoli, UNHCR reported. It capsized as desperate passengers rushed to one side, seeking rescue by the Tunisian coast guard and fishing boats that had approached the vessel. This appears to be one of the worst and the deadliest incidents in the Mediterranean so far this year, Adrian Edwards, the UNHCR spokesperson in Geneva, told reporters. Edwards noted that the rescue operation by the Tunisian authorities is still continuing. Libya has been engulfed by fighting since a pro-democracy movement opposed to the regime of Muammar al-Qadhafi emerged in February following similar protests in Tunisia, Egypt and other countries across North Africa and the Middle East. Boats loaded with migrants fleeing the ongoing conflict in Libya have been making the journey to Italy and Malta over recent months, sometimes with tragic consequences. Just last month, hundreds died as a vessel carrying about 600 people broke up shortly after departing Tripoli.