Acclaimed and revered singer/songwriter/session musician Leon Russell has died at the age of 74, it was announced on his Facebook page Sunday morning. His wife reported that Russell passed in his sleep:

A post on his official site shared more details:
Leon Russell died on Nov. 13, 2016 in Nashville at the age of 74. His wife said that he passed away in his sleep.
The Master Of Space And Time was a legendary musician and songwriter originally from Tulsa, Oklahoma who performed his gospel-infused southern boogie piano rock, blues, and country music for over 50 years.
Leon was inducted into both the Rock and Roll Hall Of Fame and the Songwriter’s Hall of Fame in 2011.
Leon led the famous Joe Cocker’s ‘Mad Dogs & Englishmen’ tour and performed with George Harrison and Friends at the Concert For Bangladesh. Leon has also toured with Delaney & Bonnie and Friends, Edgar Winter, The New Grass Revival, Willie Nelson, and Sir Elton John.
Leon’s songwriting credits include ‘A Song For You’, ‘Delta Lady’, ‘Hummingbird’, ‘Lady Blue’, ‘Back To The Island’, ‘Tight Rope’, and ‘This Masquerade’.
Russell’s death comes at a time in which he was still very much a touring and performing artist, with several shows line up in the coming months, so this sad news comes at quite a shock in that regard.

Rest in peace, Leon.