US Marines fought several firefights in the Haitian capital, and believe two Haiti fighters may have been killed outside the prime minister's residence, a spokesman said. The first incident occurred late Tuesday just after Gerard Latortue was named Haiti's new prime minister as part of efforts to resolve the Caribbean country's political crisis. The firefights also came as the US-led multinational force in Haiti prepared to join police in a campaign to get weapons off the streets of Port-au-Prince. "There were three incidents last night where gunmen fired at Marines who in all three cases returned fire," said spokesman Major Richard Crusan. In one, gunmen opened fire on Marines who were patroling outside the prime minister's residence. US troops fired back and thought they killed two people, but when they returned to the scene about three hours later they did not find the bodies, which may have been removed by the attackers, Crusan told AFP. When the Marines returned to the scene they were again fired upon, and attackers later also fired automatic weapons at the residence, the spokesman said. At about 11:00 pm (0400 GMT Wednesday) US Marines guarding the port came under fire from at least one gunman, who fled on foot with two others, said Crusan. US Marines have killed two Haitians in recent days. One was shooting at the presidential palace and another failed to stop at a military roadblock, according to the military. The multinational force of more than 2,500 troops has conducted daily patrols, secured key installations and in some cases assisted police in stopping looting. The troops now plan to help get guns off the streets. **PHOTO CAPTION*** Two US marines post guard on the front lawn of the presidential palace in Port-au-Prince. (AFP/Jaime Razuri)