Christopher Reeve, the screen and stage actor who starred in "Superman" films and who became an international advocate for spinal cord research after a near-fatal equestrian accident nine years ago in Culpeper, Va., died Sunday of heart failure, the Associated Press reported early today. He was 52.

Reeve fell into a coma Saturday after going into cardiac arrest at his New York home, his publicist, Wesley Combs, said last night.

Combs said in a statement that Reeve was being treated for a pressure wound, a common complication for people living with paralysis. In the past week, the wound had become severely infected, resulting in a serious systemic infection. Reeve was admitted to Northern Westchester Hospital on Saturday evening and never regained consciousness, according to the statement. His family was at his side when he died.

In a statement, Dana Reeve, his wife, thanked his healthcare providers and fans "who have supported and loved my husband over the years."

"The family asks that you respect their privacy at this very difficult time," Combs said.

Reeve was born in New York on Sept. 25, 1952, and graduated from Cornell University in Ithaca. He also studied drama at the Juilliard School. After his accident he appeared in a made-for-television production of "Rear Window" and directed an HBO feature called "In the Gloaming."

Survivors include his wife, mother and father, a brother and three children.