His representative has called the death “sudden and unexpected.”

Chris Cornell, lead singer in Soundgarden and Audioslave, has died aged 52.

In a statement to The Associated Press, Cornell’s representative Brian Bumbery said he died on Wednesday night (May 17) in Detroit, reports ABC.

Bumbery called the news “sudden and unexpected” and the cause of death is not currently known. Cornell’s family are asking for privacy while they work with medical professionals to determine the cause.

Soundgarden was formed in 1984 by Cornell, bassist Hiro Yamamoto and guitarist Kim Thayil. They released six albums during their career, including 1994’s breakthrough fourth album Superunknown, and are one of the undisputed titans of the grunge movement.

Cornell formed supergroup Audioslave in 2001 with lead guitarist Tom Morello, bassist Tim Commerford and drummer Brad Wilk. They made history in 2005 when they played a free concert in Cuba for over 70,000 people, the second American rock band that had been allowed to perform in the country at the time. The band released three albums, before splitting up in 2007.