CAHOKIA, Ill. (AP) — Authorities say an Illinois World War II veteran found dead in a burning home died from a blow to the head.

The St. Clair County Coroner’s Office on Tuesday announced the preliminary cause of death as blunt force trauma for 89-year-old Howard Sutton of Cahokia. Sutton was found dead in a house fire Oct. 18. Authorities are investigating the death as homicide. Full autopsy results have not yet been released.

The Major Case Squad of Greater St. Louis was activated after the fire. It hasn’t released further information on the case.

Firefighters responding to the blaze were forced from the home by exploding ammunition. They recovered Sutton’s body once the fire was under control. No firefighters were hurt.

Sutton’s daughter said Sutton was stationed in the South Pacific with the U.S. Navy during World War II.