U.S. marines confirmed Monday they had shot and killed a suspected pro-Aristide militant who was part of group of militants who fired on a demonstration Sunday, in which six people were killed. Among the dead was Spanish television journalist, Ricardo Ortega. Multinational forces in Haiti say their mission will not change as a result of Sunday's violence.

U.S. Marines who make up the bulk of the multinational force in Haiti say they engaged gunmen twice on Sunday when suspected militants loyal to former President Jean-Bertrand Aristide attacked a large crowd of demonstrators who had gathered in front of the National Palace.

U.S. Marine colonel Mark Garganus, who heads the multinational force in Haiti, said Marines responded according to proper rules of engagement.

Colonel Garganus said he understands how some Haitians are frustrated with the multinational troops after Sunday's violence. "I think the people yesterday were clearly frustrated because it was a situation that was all too common for them, and it was a situation that they hoped we could resolve immediately. We cannot resolve those situations immediately," he said.

Colonel Garganus said Sunday's violence does not change the multinational mission which is to work with Haiti's police to establish security.

As far as disarming the gangs that allegedly carried out Sunday's violence, Colonel Garganus said he will give all possible help to the Haitian police to accomplish that goal. "Disarmament is not part of my stated mission. It is a police function. However with that said, we will work very closely in cooperation with the Haitian National Police. Once they take the decision that they are going to take the lead on disarmament, we will help them enforce their disarmament policies," he said.

Speaking to the Reuters news agency on Monday, newly-appointed Haitian police chief Leonce Charles confirmed Haitian police will soon begin disarmament operations against armed gangs in the city.

Security was again tested on Monday when hundreds of looters were not stopped as they ransacked a warehouse areas adjacent to the Port-au-Prince airport where the multinational troops are headquartered.

Meanwhile Former Haitian Chief Justice Boniface Alexandre was formally sworn in Haiti's new interim president on Monday. Mr. Alexandre was sworn in behind closed doors, in the hours following Jean Bertrand Aristide's departure from Haiti on February 29. Monday's ceremony was described by U.S. and Haitian officials as a formalization of his presidency. In remarks during the swearing in, Mr. Alexandre called for national reconciliation and new elections.