The 'horrifying' aftermath of a deadly helicopter crash which killed six people - including musician Oliver Tree - has been described by eyewitnesses in Brazil. All six people on board the helicopter died after the deadly incident in Rio De Janeiro , where two helicopters collided in mid-air. Rio de Janeiro’s Military Fire Department said one of the helicopters crashed on the parking lot of a car dealership , where several electric vehicles were parked, igniting a fire that was extinguished.