Updated

Kentucky State Police say preliminary autopsies show two adults found in the aftermath of a suspicious residential fire had been shot to death.

In a statement Thursday, police say the autopsies reveal that 29-year-old Bulmaro Arellano and 24-year-old Marisol Hernandez died as a result of gunshot wounds. Their bodies and the bodies of two children were found Tuesday after authorities responded to a report of a fire at a home in Murray.

Police say it's believed both children, identified as a boy about 5 years old and a girl about 1 year old, had succumbed to smoke inhalation, pending further testing.

Police say the investigation shows that the fire was intentionally set to cover up the killings. The investigation continues.