Comedian and musician Neil Innes, who collaborated with Monty Python and played with The Rutles, has died aged 75, his agent has said.
His death was unexpected and he had not been ill, Nigel Morton told the PA news agency.
The writer performed and penned songs and sketches for the Pythons' final TV series in 1974 after John Cleese temporarily left. He also wrote songs for Monty Python And The Holy Grail.
Innes was a frequent collaborator with the comedy group and toured the UK and Canada with them.
He was only one of two non-Pythons to be credited as a writer for the TV series, alongside Douglas Adams.
He also appeared in Monty Python's Life Of Brian and Terry Gilliam's Jabberwocky before joining with Eric Idle on the sketch show Rutland Weekend Television, about a fictional low-budget regional TV station.
This show spawned The Rutles, a spoof of the Beatles, in which Innes played the character of Ron Nasty, who was based on John Lennon.
In a statement, the family of Neil Innes said: "It is with deep sorrow and great sadness that we have to announce the death of Neil James Innes on 29th December 2019.
"We have lost a beautiful kind, gentle soul whose music and songs touched the heart of everyone and whose intellect and search for truth inspired us all.
"He died of natural causes quickly without warning and, I think, without pain.
"His wife Yvonne and their three sons Miles, Luke and Barney and three grandchildren Max Issy and Zac give thanks for his life, for his music and for the joy he gave us all."