LOS ANGELES • George Kennedy, the Oscar-winning star of Cool Hand Luke and the Naked Gun comedy movies, has died at the age of 91.

The burly American actor - famed for his tough-guy roles before playing against type later in his career - died on Sunday morning in Boise, Idaho, grandson Cory Schenkel said on his Facebook page.

"I have travelled on many business trips and movie shoots with my grandpa... I have created so many great memories and I will enjoy them for life," he said.

"While I am extremely sad that they are both gone - my grandma (on) September 14 and my grandpa this morning - I am grateful for the life, memories and knowledge they shared with me."

The Idaho Statesman said the 1.93m-tall actor died of natural causes, citing Canyon County Coroner Vicki DeGeus-Morris. "He had a history of heart problems," it quoted her as saying.

Kennedy often played second billing to the likes of actors Frank Sinatra, Cary Grant, Gregory Peck, James Stewart, Robert Mitchum and, on several occasions, Clint Eastwood.

He won a Best Supporting Actor Oscar as a sadistic chain gang prisoner in 1968 for Cool Hand Luke. In one scene, he gets to clobber Paul Newman, who played fellow prisoner Luke.

He starred in more than 200 films and television series, including the 1974 disaster movies Airport 1975 and Earthquake (1974), and long-running soap opera Dallas. He was best known in his later career for playing bumbling police captain Ed Hocken in The Naked Gun spoof cop series, from 1988 to 1994.

Actor-comedian Albert Brooks led the online tributes, tweeting: "R.I.P. George Kennedy. Lucky enough to work with him in Modern Romance. Great guy."

Tarzan actress Bo Derek tweeted: "Rest in peace - friend. I miss you."

The Hollywood Chamber of Commerce said flowers would be placed on his star on the Walk of Fame.

AGENCE FRANCE-PRESSE, REUTERS