UPDATED | June 19, 2017 3:05 PM

DENTON COUNTY (CBSDFW.COM) – Authorities say a couple in their 60’s was found murdered at a home in Sanger, and their grandson in his 20’s was also found dead.

According to police, the man in his 20’s stabbed the couple to death and then stabbed and killed himself. The Denton County Sheriff’s Office says the three lived together in the home.

Neighbors say it was a grandson and his grandparents in what police are calling a double murder-suicide, but there has been no confirmation on the relationship between the deceased.

Authorities say a relative found the bodies Saturday night. Neighbors also say a retired doctors, another neighbor, rushed in and tried to help.

“He and another neighbor were walking in last night, and he heard the screams of the man who found the bodies,” said neighbor Bob Billups. “We’ve all lost people we love, but to lose three at one time, my prayers go out to the family.”

The victims have been identified as Douglas P. Greeney born in 1946 and his wife Glady’s G. Greeney born in 1950. The suspect, Ryan D. McGraw, was born in 1991.

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