US musician Oliver Tree believed to be among six dead in mid-air helicopter crash in Brazil

US musician Oliver Tree is believed to be among six people dead after a mid-air collision between two helicopters in Rio de Janeiro.

The city's military fire department says one of the helicopters crashed in a car dealership where several electric vehicles were parked, igniting a fire which was later extinguished.

Officials say an investigation is under way into the cause of the collision.

Police say 32-year-old Tree, an alternative singer and internet personality, was on the list of passengers handed to aviation authorities, but the bodies of those killed in the crash have yet to be identified.

Tyre repair worker Fernandes de Freitas told local media he saw one of the helicopters in flames following the collision and noticed one of the passengers had jumped out of the other aircraft before hitting the ground.

"It was terrifying, absolutely horrifying," De Freitas said.

Tree was in Brazil as part of a world tour when the crash occurred, where he was due to play more than 70 shows across 30 countries.

He had performed in Buenos Aires on 4 June and published a video on Saturday playing football in a local neighbourhood of Rio.

The other names on the list of passengers were Argentine YouTuber Gaspar Prim, known online as "Gaspi", a Brazilian producer and an Argentine film director, along with the pilots of both helicopters.

Read more on Sky News:
Three dead after Royal Navy helicopter crashes into Devon field
Helicopter crash in Borneo, Indonesia, kills eight

Internet personality KSI and judge on ITV's Britain's Got Talent paid tribute to Tree on his social media, posting a series of pictures of the two together.

"Can't believe I'm actually having to type this. You're 32 man. You should still be here. You still had so much life to live. So much music to make. So much content to make. You're a legend and will always be a legend. Still doesn't feel real. Genuinely feel sick. I love you bro," said KSI, accompanied by a love heart emoji.

Tree was known for songs including Life Goes On, Miss You, Alien Boy and Voices, the latter of which he sang alongside KSI.

Miss You, in which he featured as the main artist along with German producer Robin Schulz, was nominated for Best International Song at the 2024 Brit Awards.

The track peaked at Number 3 in the UK singles chart, and No 4 in the Australian charts.

His debut album, Ugly Is Beautiful, peaked at Number 14 in the US album charts and Number 42 in the UK charts.

Tree also has a Guinness World Record for the largest kick scooter, measuring at 4.16m tall and 3.13m long.

(c) Sky News 2026: US musician Oliver Tree believed to be among six dead in mid-air helicopter crash in Brazil