ROCHESTER, N.Y.—Serial killer Arthur Shawcross, who was serving life in prison for strangling 11 women in the Rochester area, has died at 63.

Shawcross died late Monday at an Albany hospital, where he had been taken after complaining of leg pain earlier in the day at the Sullivan Correctional Facility, Corrections Department spokesman Erik Kriss said Tuesday. The cause of death was still under investigation, he said.

Shawcross’ 13-week trial for 10 of the killings included graphic testimony about mutilation and cannibalism.

Shawcross’ victims, most of them prostitutes, were killed from March 1988 to January 1990. At the time, he was on parole after serving 15 years in prison for killing two children in northern New York’s Watertown in 1972.

Shawcross was arrested in January 1990, a day after state police spotted him near the frozen body of one of his victims.

He was convicted of killing 10 of the women in December 1990. Jurors rejected defense arguments that he was legally insane at the time of the killings because of brain damage, abuse during childhood and his experiences as a soldier in Vietnam.

Three months later, Shawcross pleaded guilty to strangling a woman whose body was found Nov. 27, 1989, in woods in neighboring Wayne County.

He did not testify, but jurors were shown videotapes of him being interviewed under hypnosis by a defense psychiatrist, Dr. Dorothy Lewis. He switched in and out of a high-pitched woman’s voice and told Lewis he had once been a cannibal in medieval England. He also described childhood incestuous relations and wartime atrocities and cannibalism in Vietnam.

He told Lewis his mother’s voice told him to kill his victims. But in videotaped interviews with prosecution psychiatrist Dr. Park Dietz, Shawcross said he never heard voices or had different personalities.