Forsyth, IL (WAND) -A couple found dead inside their Forsyth home on Monday were shot to death, according to the Macon County Sheriff’s Department.

The office said autopsy reports for 65-year-old Dr. William Frame and 63-year-old Lorie Frame were conducted Wednesday in Bloomington. The results showed that both died from a single gunshot.

But the manner of their deaths still has not been released.

The sheriff’s office said Thursday it is working to “…diligently investigate this case to determine exactly how the Frames were killed.”

No arrests have been made.

The Frames, who police said were married, were found dead Monday in their home on Malinda Ct. Police said they were called to the home for a welfare check. Police have not said who called them and made the welfare check request or why.

Previously, the sheriff’s office said there was no threat to the public, but did not elaborate.