At least 16 royal guardsmen have been killed in Morocco after their bus plunged into a ravine, media reports and doctors say. Security sources said the driver lost control of the bus at a bend in the road, causing the bus to overturn.   More than 40 other guardsmen were injured in the crash near al-Hoceima in the north of the country. The guardsmen were reportedly travelling north to prepare for a visit by King Mohammed V The injured were transferred to al-Hoceima regional hospital for treatment. The 6,000-strong Moroccan Royal Guard is part of the military but its sole function is royal security. The Moroccan news agency MAP reported that the king had announced after the accident that he would cover the medical and funeral costs for the families affected.