Kelley, 57, was found dead in the bathtub of his home in South Pasadena by a friend on Tuesday night, Los Angeles County Coroner's spokesman Ed Winter said.

Winter said the artist had last been seen alive on Sunday. No suicide note was found in the home and there were no signs of trauma or foul play, he said. An autopsy was scheduled for Thursday.

"It's a terrible loss for his family and friends and for the artists of this community, which he's done so much to change and enrich," Paul Schimmel, chief curator for the Los Angeles County Museum of Contemporary Art, told Reuters.

"More than any other artist of his generation, he changed the perception of this city and helped make it the great international art city it is today," he said.

Schimmel, who had known Kelley since 1981, said he was stunned by the artist's death and the possibility that he may have taken his own life.

"I saw Mike just before the holidays and had just a wonderful evening with him," Schimmel said. "He was thinking about important opportunities for change in his life going forward, so this all comes as a terrible, tragic shock."

Kelley, born in a suburb of Detroit in 1954, was a founding member of the band Destroy All Monsters in the mid-1970s before moving to California and attending the California Institute of the Arts.

In addition to his art, Kelley was known as a "tireless advocate" for other artists who wrote extensively about the subject, Schimmel said.

"He was an artist who drew upon all the arts in terms of music, film, performance, drawing, sculpture and installation to simultaneously create a kind of visual and intellectual assault on your senses," he said.

(Reporting by Dan Whitcomb; Editing by Cynthia Johnston)

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