TRIPOLI (Reuters) - Nato planes pounded Libyan government weapons depots southeast of the town of Zintan on Monday, in a sign of widening conflict in the Western Mountains region as rebels battle to unseat Muammar Gaddafi. "The air strikes occurred around 1100 (5 a.m. EDT). We saw big plumes of smoke and heard explosions," said a rebel spokesman in Zintan who gave his name as Abdulrahman. There was no immediate comment from NATO or from Tripoli. Two months into a conflict linked to this year's uprisings in other Arab countries, rebels hold Benghazi and towns in the east while the government is firmly in control of the capital and other major cities. Tripoli says most Libyans support Gaddafi, the rebels are armed criminals and al Qaeda militants, and NATO's intervention is an act of colonial aggression by Western powers seeking to steal the country's oil. The rebels face a government with superior firepower and resources but they achieved a financial breakthrough on Monday, selling oil worth $100 million paid for through a Qatari bank in US dollars, a member of their oil and gas support group said. They desperately need money for food and medicine, and this prompted Western and Arab countries last week to promise a cash lifeline potentially worth billions of dollars. In another boost, Egyptian authorities put Gaddafi's cousin Ahmed Gaddaf al-Dam under house arrest in the city of Nasr and planned to seize his funds and property and deport him to Benghazi, according to the rebel Brnieq website, which cited a reliable source. A stalemate prevails in much of Libya and the war is increasingly focused on Misrata, the last city in the west held by rebels who cling on in the face of a government siege and weeks of ferocious battles that continued on Monday. "There is fighting now in the east, west and south of Misrata. This includes the areas of al-Ghiran, Bourouya and Zeriq," a rebel spokesman called Reda said from Misrata. "There is fighting also near the airport. The revolutionaries control the western side while the brigades are still holding the southeastern side of the airport. NATO struck today in the areas of Tamina and Chantine, east of the city," Reda told Reuters by telephone. Another rebel spokesman in Misrata, Abdelsalam, echoed his comments and said rebels were still trying to extinguish fires at a fuel storage depot bombarded by the government on Friday. The attack provoked fuel shortages, he said. A ship chartered by the International Committee of the Red Cross arrived in Misrata on Monday, bring medical supplies, spare parts to repair water and electrical systems and baby food, the organization said. Evidence of mounting conflict in the Western Mountains came at a small clinic in the Tunisian frontier town of Dehiba. Rebels seized the Dehiba border crossing in April, opening a conduit for supplies going in and a point of departure for wounded fighters from Zintan seeking treatment. Most at the clinic had been shot at close quarters as they tried to hold back loyalists east of Zintan, a town in rebel hands. Eleven died on Saturday alone, their names displayed at a refugee camp in Dehiba that lodges their families. "They are heroes, they are Mujahideen," said Jamal Maghroub, whose nephew was among those killed. New York-based Human Rights Watch accused loyalist forces on Monday of "repeated indiscriminate attacks" on residential areas in the mountain towns of Nalut, Takut and Zintan. The war has killed thousands and caused extensive suffering, not least for tens of thousands of economic migrants from sub-Saharan Africa forced to flee overland or by boat. Dozens have died trying to reach Italy and migrants brought to safety on the Italian island of Lampedusa at the weekend said they saw a boat carrying 500-600 people foundering off Libya late last week and bodies being washed ashore. One Somali woman told International Organization for Migration (IOM) staff on Lampedusa she and her four-month-old baby were on a boat that sank between Thursday and Friday last week. The woman lost her baby but swam to shore and then board another boat heading to Italy. "She was in a state of shock when she arrived on Lampedusa," said IOM's Daria Storia. The migration presents a political headache for the European Union and NATO, which denied a report that alliance units failed to help a drifting boat carrying African migrants, leading to the deaths of 62 people from thirst and hunger. France also denied that its aircraft carrier Charles de Gaulle was involved in the incident. The boat carrying 72 people, including several women, young children and political refugees, ran into trouble after leaving Tripoli for Lampedusa on March 25, the British Guardian newspaper said. There was no independent confirmation of the incident but a spokesman for the Italian coastguard said the location of the ship was pinpointed with the help of satellite telephone providers and was heading toward Maltese waters.