Two UN consultants, one from Britain and the other from Canada, were shot dead in Somalia's semi-autonomous Puntland region.
A mentally ill security guard shot the two men Monday as they arrived at an airport in the city of Galkayo, Puntland President Abdiweli Mohamed Ali told VOA's Somali Service.
The president said the man was immediately arrested by police and an investigation is under way.
The names of the two victims have not been released. According to the UN mission in Somalia, they worked for the United Nations Office on Drugs and Crime.
Ali said the two had come to Puntland to help with construction of a prison.
In a statement, UN representative to Somalia Nicholas Kay condemned the murders and said the United Nations remains committed to supporting the Somali people as they emerge from decades of conflict.