Steve Clark, 30, guitarist for heavy metal group Def Leppard, was found dead at his London home Jan. 8. Cause was unknown, pending an autopsy, but friends said death followed a heavy-drinking party the night before.

Clark was found by his girlfriend on the living room floor at his home on Old Church Street, in the fashionable Chelsea district of London, police said. Authorities said he died in his sleep.

Def Leppard was started in a garage in Sheffield, northern England, in January 1978 by lead singer Joe Elliott, bassist Rick Savage and Clark. Group was signed to Polygram in 1979 and quickly built a reputation based on strong guitar work and soaring harmonies.

In 1989, the last year the band toured, it reportedly earned $28 million. It has released four albums since its inception, including the multiplatinum “Pyromania” and “Hysteria.”

“He was a really quiet, shy, humble, nice, gentle sort of bloke,” Elliot said. “Onstage, he was the business. He was very visual and very energetic, a great person to be alongside.”

Elliot said the group was to continue recording a new LP, “but obviously that isn’t going to happen. But the band will carry on eventually.”

Clark recently was rumored to have entered an alcohol rehabilitation program, delaying the recording of the next Leppard album.

Survived by his parents and a brother.

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