The actor, who became known for his role as ruthless tycoon Palmer Cortland on longrunning U.S. TV series All My Children, passed away at Cedars-Sinai Medical Center in Los Angeles on Friday (22Jan10) at the age of 89.
His partner Albert Wolsky confirms Mitchell had been suffering from chronic obstructive pulmonary disease for years and was recently hospitalised after experiencing problems when he was struck down with pneumonia.
Mitchell joined the popular soap opera in 1979 and stepped down as a series regular in 2008. However, he returned to the small screen earlier this month (Jan10) to help the cast and crew celebrate its 40th anniversary episode.
Before establishing himself on the show, Mitchell - who started out as a dancer - had a stint on Broadway in plays like Billion Dollar Baby, Brigadoon and Carousel, and appeared in movies including Deep In My Heart (1954), Oklahoma (1955) and The Band Wagon with Fred Astaire in 1953.
He also shared his skills with younger generations by teaching classes at the prestigious Yale University in Connecticut and Drake University in Iowa.