ATMORE, Ala. (AP) — A man convicted in the killing of his 4-month-old son has died on Alabama’s death row, state corrections officials said.

The Alabama Department of Corrections, in a statement Friday to The Associated Press, confirmed corrections officers found John Michael Ward, 58, unresponsive late Tuesday in his cell at Holman Correctional Facility in Atmore.

Ward was transported to a medical facility “where life-saving measures were unsuccessfully performed,” the department said.

Physicians pronounced Ward dead on Wednesday, the department said. A cause of death is pending an autopsy and conclusion of an investigation by the ADOC’s Law Enforcement Services Division, officials said.

Ward had been on death row for 26 years and four months, according to the ADOC, after a Baldwin County jury sentenced him to death in December 1998 for the murder of his infant son who, court records show, was smothered in January 1997, al.com reported.