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.

Although he had been making music for over 15 years, he didn’t find crossover success until the late 2010s with singles like “Hurt,” “Cash Machine,” and “Let Me Down” leapfrogging each other in popula...