The deaths of a couple found early Sunday in their burning DeKalb County home have been ruled a murder-suicide, according to authorities.

William M. Kreda, 75, and Marjory R. Kreda, 76, were found dead inside their home when emergency crews responded to the fire about 1:40 a.m. at 3355 Gurler Road in rural Malta, according to the DeKalb County Sheriff’s Office.

Crews found the couple’s house and barn on fire after it was called in by a person who spotted the flames while traveling on Interstate 88, authorities said.

Autopsies conducted Monday by the DeKalb County Coroner’s Office determined both died of gunshot wounds.

Investigators believe William Kreda fatally shot his wife in their second-floor bedroom before he set set their barn and a shed on fire.

The fire set inside the home was determined to have “multiple origins,” authorities said. Kreda set the fires inside the home before returning to the couple’s bedroom and shooting himself. Both were found dead in their bed.

The investigation was ongoing.