Keith Emerson, the keyboardist and founder of Emerson, Lake & Palmer, was found by his girlfriend on Thursday in the couple’s home in Santa Monica, Calif., with a bullet in his head, seemingly self-caused. The suicide investigation had just begun, but his girlfriend, Mary Kawaguchi, 52, reports that Emerson had been depressed because a of a nerve problem in his right hand which severely impaired his ability to play on the keyboard. The 71-year-old had been “tormented with worry” about his upcoming concerts in Japan.

“Keith wasn’t feeling well on Thursday night. He had bronchitis so I tucked him up in bed,” said Kawaguchi. “He was sleeping when I left and I thought he was sleeping when I got back, but then I realized what had happened.”

She also added that he was a very “sensitive soul” and was very affected by the criticism he read from concert-goers last year who left mean comments such as “I wish he would stop playing.”

Emerson was a keyboardist for many bands in the 1960s, but is most famously a founder of the progressive rock band was best known for the hits “Nut Rocker, Fanfare for the common Man,” “Lucky Man,” “Tarkus” and “Karn Evil 9.” Emerson, Lake & Palmer received its first and only Grammy nomination in 1972 for Best New Artist.

The band wrote about Emerson on the official Facebook site:

Keith Emerson (1944 – 2016)We regret to announce that Keith Emerson died last night at his home in Santa Monica, Los…

Posted by Emerson, Lake & Palmer on Friday, March 11, 2016

And band member Carl Palmer stated that Emerson was his “brother-in-music” and “a gentle soul whose love for music and passion for his performance as a keyboard player will remain unmatched for years to come.”

I am deeply saddened to learn of the passing of my good friend and brother-in-music, KEITH EMERSON. Keith was a gentle…

Posted by Carl Palmer on Friday, March 11, 2016

Palmer also posted today that he will be continue to playing music and promises a tribute show to Emerson in the future.

‘To everyone who posted such wonderfully kind thoughts and tributes following Keith’s tragic death I would like to say…

Posted by Carl Palmer on Sunday, March 13, 2016

Emerson had planned to retire after the upcoming shows in Japan.

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