Legendary American musician Tom Petty has died at the age of 66 after suffering a heart attack at his Malibu home.

Petty, front man of the band Tom Petty and The Heartbreakers, sold more than 80 million albums worldwide and had hits such as Free Fallin' and I Won't Back Down.

TMZ reported Petty was found unconscious at his Malibu home on Sunday.

The singer's spokesperson, Carla Sacks, reported he died on Monday night at UCLA Medical Centre in Los Angeles.

Tom Petty and The Heartbreakers had just finished a 40th anniversary tour with a final concert at the Hollywood Bowl one week ago.

Petty marked the moment with an Instagram post thanking the Los Angeles crowd.

Speaking to Rolling Stone last year, Petty hinted that his most recent tour would be his last.

"I'm thinking it may be the last trip around the country," Petty told the magazine.

"We're all on the backside of our 60s.

"I have a granddaughter now I'd like to see as much as I can.

"I don't want to spend my life on the road.

This tour will take me away for four months.

"With a little kid, that's a lot of time."