Soundgarden frontman Chris Cornell died by suicide, the Wayne County Medical Examiner's Office said on Thursday.

Cornell (52) was found dead in his Detroit hotel bathroom on Wednesday night after playing a concert in the city with the grunge band.

“A full autopsy report has not yet been completed,” the Medical Examiner’s Office said in a statement after conducting an initial autopsy which confirmed the death was a suicide.

Cornell's publicist Brian Bumbery said earlier that the singer's death was "sudden and unexpected."

Detroit police spokesman Dan Donakowski said that officers were called to Cornell's hotel around midnight by a friend of the musician and found Cornell "laying in his bathroom, unresponsive and he had passed away."

Cornell, the lead singer of Soundgarden, Audioslave and also a successful solo artist, had tweeted earlier on Wednesday about enjoying the camaraderie of being back on tour with the band, which was in the middle of a US tour.

Mainstream success

Soundgarden was one of the leading bands in the grunge music movement in the 1980s and 1990s, releasing albums such as “Badmotorfinger” and the Grammy-winning “Superunknown,” which brought the band mainstream music scene success.

Cornell had spoken openly in interviews of his struggles with drugs as a teenager, and later with alcohol. But he said in 2007 that he had been sober since checking himself into rehab in 2002. He also spoke of periods of depression and agoraphobia.

Soundgarden broke up in 1997 and Cornell in 2001 joined members of Rage Against The Machine to form Audioslave, which earned acclaim with its self-titled album. They reunited in 2010 and embarked on the current US tour in April.

Led Zeppelin guitarist Jimmy Page led tributes on Thursday to Cornell, calling him "Incredibly Talented, Incredibly Young, Incredibly Missed" in a Twitter post.

Kiss singer Paul Stanley tweeted he was "Stunned to hear the death of Chris Cornell," while Aerosmith's Joe Perry called his passing "a sad loss of a great talent to the world."

Alice Cooper lauded him as "the best voice in rock and roll", while Sir Elton John described him as "the loveliest man".

‘The Voice’

The School’s Out singer said on Thursday: “Chris Cornell, in our circle, was known as The Voice because he had the best voice in rock and roll.

“I was lucky enough to write and record two songs with him. His death comes as a total shock to all of us.

“Black Hole Sun will live on as a classic, and his is a true legacy of rock and roll.”

Sir Elton posted a picture of Cornell on Instagram, with the caption: "Shocked and saddened by the sudden death of Chris Cornell. A great singer, songwriter and the loveliest man."

Producer Nile Rodgers described Cornell as “my special brother”.

He said in a statement to the Press Association that he could not process news of his death.

“I was asleep and my phone was jumping and one of our mutual friends - they were crying and bawling - and said ‘Nile you won’t believe this’ and he said ‘Chris is dead’, I said ‘Chris who?’

“Chris Cornell, he’s like 12 years younger than me, he’s my friend and we’d go out together for dinner. We’d have dinner and laugh and joke and talk about the world,” Rodgers said.

“I’m shocked, I don’t even know how to deal with it.”

Singer-songwriter Billy Idol tweeted: "Sad to hear of Chris Cornell passing, great singer and artist ... another blow ...RIP."

PA/Reuters