Oliver Tree, the eccentric singer known for viral hits like “Alien Boy” and “Life Goes On,” has died at the age of 32 following a helicopter crash in Rio de Janeiro.

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.

American singer Oliver Tree was among those listed on the passenger list filed with aviation authorities for one of the helicopters that crashed into the parking lot of a car dealership, although poli...