Two helicopters collided over Rio de Janeiro on Sunday morning and crashed in the city’s western zone, killing all six people aboard, firefighters said.Subscribe to read this story ad-free Get unlimited access to ad-free articles and exclusive content.Rio de Janeiro’s Military Fire Department said that one of the helicopters crashed on a car dealership, where several electric vehicles were parked, igniting a fire that was extinguished.Officials said an investigation is underway to determine the cause of the collision.Police said that American singer and comedian Oliver Tree was on the list of passengers handed to aviation authorities, but have not been able to identify the bodies of those killed in the crash.ShareAdd NBC News to GoogleThe Associated PressThe Associated Press...