Eleven people, including three children, are dead and six others missing after a ferry sank on Lake Titicaca in western Bolivia, according to the Bolivian Navy. The boat was carrying 26 people when the tragedy occured Tuesday night near Suriqui Island in the southeast of the world\'s highest navigable lake on the border of Bolivia and Peru, the navy said Wednesday. Nine people were rescued, and rescue work was still under way. The boat was carrying a group of students and their teachers back to mainland after taking part in an annual commencement ceremony on the island. Initial investigation pointed to overloading as the cause of the accident, said police, who have launched an investigation.