John Mahoney, the English-born actor who played Frasier and Niles Crane's dad Martin on 'Frasier', died on Sunday. He was 77.

Apart from his role in the hit sitcom, Mahoney had a rich background in theatre, undertaking many roles on Broadway and on Chicago's theatre scene. His other television and film work included In the Line of Fire, Reality Bites and Say Anything..., as well as roles in the Coen Brothers' Barton Fink and The Hudsucker Proxy.

He also voiced many characters in animated films, including The Iron Giant and Antz, and even had a role on The Simpsons, reprising his role as the father of Kelsey Grammar's Sideshow Bob,  Dr. Robert Terwiiliger, Sr.

He had suffered from colon cancer in the 1980s but his cause of death has not been revealed - only that he had been suffering from 'a short illness'. He was unmarried and had no children.

RIP.