Musician Billy Preston, a so-called "fifth Beatle," has died in Arizona at the age of 59 after a long illness.
A native of Houston, Texas, Preston played while in his teens with Mahalia Jackson, Little Richard and Ray Charles.
He later backed up the Beatles, playing keyboards on Let It Be, The White Album and Abbey Road. He also played on the hit Beatles single Get Back.
As a soloist, Preston topped the record charts in the early 1970s with Outta Space, Will It Go Round in Circles, and Nothing from Nothing.
He joined the Rolling Stones on tour and backed them up on Can't You Hear Me Knocking and Heartbreaker.
He also wrote the Joe Cocker hit You Are So Beautiful, and collaborated with Aretha Franklin, Bob Dylan, Quincy Jones, and Barbra Streisand.
He won two Grammys, including one for his involvement in the Concert for Bangladesh, staged by ex-Beatle George Harrison in 1971. Last year, in one of his final appearances, Preston performed in Los Angeles with former Beatle Ringo Starr and Harrison's son, Dhani.
Plagued by drug and alcohol abuse, Preston had scrapes with the law on narcotics and other charges. He suffered from chronic kidney failure, and had been in a coma since November.