Haiti's President Michel Martelly has “vigorously condemned” an apparent sexual assault of a young man by United Nations troops.

The Uruguay government has dismissed a naval officer and recalled five of its soldiers after a video taken on a cell phone showed several Uruguayans taking part in what appeared to be an attack on an 18-year-old man.

Mr. Martelly said late Sunday he is waiting for a detailed report of the incident. The United Nations, the Haitian courts and Uruguayan authorities are investigating.

The young man in the video and his mother have testified before a Haitian magistrate.

More than 12,000 U.N. troops and police officers serve in Haiti, as part of a force created in 2004 to help stabilize the impoverished and politically volatile country. The U.N. increased the size of the force by a third last year after a devastating earthquake killed more than 220,000 people.

The relationship between the troops and the Haitian public has at times been tense. Last year, there were protests after a cholera outbreak killed more than 6,000 people. Health investigators linked the outbreak to latrines in the camp of Nepalese troops.