Six people died when a small plane that was delivering human organs for an ill patient crashed in Lake Michigan, authorities said Tuesday, according to dpa. Four doctors and the plane's two pilots died and rescuers had given up hope of finding survivors, Milwaukee, Wisconsin fire department spokesman Lawrence Jenkins said. The Cessna crashed Monday afternoon as the team left for a trip across the lake to deliver organs to a clinic at the University of Michigan in Ann Arbor. Minutes into the 40-minute flight, the plane sent a distress signal. The cause of the crash was unknown, but it was raining lightly at the time of the accident. The patient, who was to receive the transplant, was in critical condition, but privacy concerns kept doctors from revealing what sort of transplant was needed.