South Australian police believe 92-year-old man, Dennis Willshire killed his 92-year-old wife, Barbara and then took his own life at a retirement village in Adelaide's eastern suburbs.
The couple's bodies were found by police within their unit at the retirement village in Glynde this morning after they failed to respond to a routine check by nursing staff.
Paramedics and the Metropolitan Fire Service (MFS) were also called to the unit on Glen Davis Court about 8am.
Superintendent Matt Nairn from SA Police said detectives were investigating the deaths.
"At this stage, we can determine that we believe it is a murder-suicide, and at this stage we believe the man has killed potentially his wife and then taken his own life," Superintendent Nairn told reporters.
"Police are still at the scene and it is an ongoing investigation to determine the circumstances of what has occurred, but it appears rather tragic."
He said a smell of gas reported to the MFS was "not an implicating factor in this".
It is unclear when the two people died.
A spokeswoman for Lutheran Homes Group, which runs the complex, said the two people had been living in the independent retirement unit where they were found.
"Pastoral support is being offered to residents, as well as counselling support for staff," she said.
"Our thoughts and prayers are with the family and our Glynde community at this difficult time."