Marcus Wayne Chenault Jr., who killed the mother of the Rev. Dr. Martin Luther King Jr. at a Sunday service in Ebenezer Baptist Church in Atlanta in 1974, died on Saturday at a hospital in the Atlanta suburb of Riverdale. He was 44.

Mr. Chenault was serving a life sentence at the state prison in Jackson, Ga., when he suffered a stroke on Aug. 3. He never regained consciousness, a hospital spokeswoman said.

Within weeks of the slaying of Mrs. King and a 69-year-old church deacon, Edward Boykin, on June 30, 1974, Mr. Chenault was tried, convicted and sentenced to die in the electric chair. He said he had acted out of hatred for Christianity and because his god had told him to. His lawyers said he was insane.

The sentence was upheld on appeal but he was resentenced to life in prison two months ago, partly because of the King family's strong opposition to the death penalty.