John Surtees, the only man to win world championships on two wheels and four, has died at the age of 83.
The Briton won the 1964 Formula One championship with Ferrari after winning four 500cc motorcycling world titles between 1956 and 1960. He also won three 350cc world championships.
His family said in a statement that Surtees was admitted to hospital in London last month with a respiratory condition.
"We deeply mourn the loss of such an incredible, kind and loving man as well as celebrate his amazing life," the statement added.
Surtees was awarded an MBE in 1959, the same year he won the Sports Personality of the Year award, and the CBE in 2016.
He won six F1 races in 111 starts between 1960 and 1972, and also drove for Honda, Lotus, Cooper, Lola and BRM.
Surtees was world champion in the 350cc motorcycling category as well as 500cc from 1958-60.
He later set up his own F1 team and was behind the wheel when it made its debut at the 1970 British Grand Prix at Brands Hatch.
Team Surtees managed two podium finishes but never won a race before folding in 1978.
Surtees went on to become chairman of the British team in the now-defunct A1 Grand Prix series, while his son Henry began competing in Formula Two but was killed in an accident at Brands Hatch in 2009, aged 18.
The family set up the Henry Surtees Foundation in aid of people recovering from brain and physical injuries and to support motorsport-related educational programmes.
Surtees remained involved in motor racing into his eighties, competing in classic car and bike events up until last year.
-Reuters and BBC