POLICE are investigating an alleged double rape onboard a migrant boat which arrived in Ibiza on Friday. The disturbing reports come days after police confirmed they believe "at least 50" migrants were tortured and bundled overboard during another crossing to the Canary Islands. Meanwhile, police in Gran Canaria said they believed “at least” 50 migrants were tortured and thrown overboard after being accused of witchcraft on a hellish boat crossing to Europe. Passengers told of a cursed ordeal where fellow migrants were beaten up and shot after being accused of witchcraft. Red Cross chiefs said after their rescue: “One of the people rescued had eaten toothpaste because it was the only thing he had.