Emerson died Thursday night in his home in Santa Monica, California, at age 71, the statement said.
On Tuesday the Los Angeles County Coroner's office ruled Emerson's death a suicide
, adding that the musician died from a self-inflicted gunshot wound to the head. Emerson had suffered from heart disease and depression, according to the autopsy report.
ELP drummer Carl Palmer confirmed the death of his longtime band mate.
"Keith was a gentle soul whose love for music and passion for his performance as a keyboard player will remain unmatched for many years to come. He was a pioneer and an innovator whose musical genius touched all of us in the worlds of rock, classical and jazz," Palmer said in a statement on social media.
"I will always remember his warm smile, good sense of humor, compelling showmanship, and dedication to his musical craft. I am very lucky to have known him and to have made the music we did, together. Rest in peace, Keith."
Emerson, Lake & Palmer was progressive rock's first supergroup, according to Billboard
. They achieved critical and commercial success with their instrumental prowess and thrilled live audiences with stage antics that often included pyrotechnics.
Emerson was widely considered one of the greatest keyboardists of his generation, fusing rock music with classical and jazz influences, first as a member of The Nice and then with ELP. He was one of the first musicians to experiment with the Moog synthesizer; his showmanship on the Moog, Hammond organ and piano became an integral component of the trio's performances.
Born on November 1, 1944, in the English town of Todmorden, Emerson was classically trained on the piano as a child and started his career playing R&B. He moved to London in his late teens and joined the band V.I.P.'s. He played with Gary Farr and the T-Bones, backing T-Bone Walker before forming The Nice, which got its big break backing soul singer P.P. Arnold.
Emerson started talking to Greg Lake, a founding member of King Crimson, about playing together in late 1969 when their bands shared a bill at the Fillmore West, according to Billboard
. The two joined forces in 1970, becoming Emerson, Lake & Palmer after recruiting Palmer, a veteran of the Crazy World of Arthur Brown and Atomic Rooster.
ELP released nine albums, the first five of which reached the Billboard 200's top 10. Their 1970 self-titled debut included the hit single "Lucky Man" and became an instant classic.
The follow-up, 1971's Tarkus, "solidified their popularity and distinctive sound -- instrumentally complicated yet sonically cohesive prog-rock mixing classical structures, improvisational jazz and electronics," according to Billboard.
After ELP broke up in 1979, Emerson and Lake continued with a new drummer as Emerson, Lake & Powell. The original trio reunited in the early 1990s to release two more albums.
In addition to his time with ELP, Emerson's career included solo albums and film scores, such as Dario Argento's 1980 horror film "Inferno" and the 1981 Sylvester Stallone thriller "Nighthawks."