ST. JOHNS COUNTY, Fla. -

The deaths of three people in a St. Johns County home on Tuesday have been ruled a double murder-suicide.

According to the St. Johns County Sheriff's Office, autopsies revealed 51-year-old Gregory Testa shot and killed his elderly parents, 87-year-old Joyce Testa and 90-year-old Raymond Test, then killed himself.

Investigators said they don't know a motive for the killings.

The bodies were found when deputies were called to check on the welfare of someone in the home in the 400 block of Gianna Way, off State Road 207 southwest of St. Augustine, about 2 p.m.

"The employer hadn't heard from one of the residents and asked us to check on his welfare," St. Johns County Sheriff's Office Cpl. Catherine Payne said.

When there was no answer at the door, deputies waited for a warrant to enter the home and found the bodies.

No one knows how long the family may have been dead because it had been a few days since Gregory Testa had shown up for work.

Neighbors said the family had moved into the house only six months ago. They said they didn't know much about the family, but they are still sad and shocked to see something like this happen.

"It's very creepy and it's shocking," neighbor Victoria August said.