Man convicted of killing Dan Gable's sister dies in prison

The man who was convicted of killing Olympic wrestler Dan Gable's sister has died in prison.

John Thomas Kyle died in a Kansas prison where he was serving a life sentence in the death of Diane Gable, according to the Iowa Department of Corrections.

He died earlier this week of a heart attack. He was 64 years old.

Authorities said Kyle was 16 when he killed 19-year-old Diane Gable in May 1964.

At the time of his death, Kyle was also serving a five-year sentence from Lee County for escape, according to he Department of Corrections.

This sentence began on October 29, 1964. Kyle's custody was transferred to the Kansas Department of Corrections following the escape return on October 23, 1981. Kyle escaped from the Iowa State Penitentiary on March 29, 1977, was apprehended in Florida and returned to Iowa custody on November 2, 1977.