Walter Matthau, the Oscar-winning star of such movies as The Fortune Cookie, The Odd Couple, Grumpy Old Men and many other hits, died Saturday morning of a heart attack.

He was 79.

Matthau was pronounced dead shortly after being brought to St. John's Health Center in Santa Monica, Calif.

Although he starred in dozens of films, it was when he teamed up with Jack Lemmon that Matthau hit his peak.

His performance in The Fortune Cookie earned him the Academy Award for best supporting actor in 1966.

He would later be nominated for a best actor Oscar for his roles in Kotch and The Sunshine Boys.

But probably his most famous role - and the one that truly brought him to international attention - was as the sloppy, slovenly, cantankerous, New York sportswriter, Oscar Madison, in Neil Simon's The Odd Couple. In the stage version he starred opposite Art Carney, but was teamed up again with Lemmon in the 1968 film version.

Matthau once told Time magazine: "Every actor looks all his life for a part that will combine his talents with his personality. The Odd Couple was mine. That was the plutonium I needed. It all started happening after that."

Before becoming an actor Matthau held jobs as a forester, a gym instructor and a boxing coach. During the Second World War he enlisted in the U.S. Army Air Corps and served as a radio cryptographer.

At the end of the war he enrolled in acting school, supporting himself on the GI Bill.

His last film saw him co-starring with with Meg Ryan, Diane Keaton and Lisa Kudrow in Hanging Up, which was released in February.

Matthau married Grace Geraldine Johnson in 1948. They divorced in 1958. They had two children, David and Jenny.

Matthau married Carol Marcus in 1959, and they had one son, Charles.