Authorities are investigating a double homicide and suicide in Sanger.

26-year-old Ryan D. McGraw killed his grandparents, 71-year-old Douglas P. Greeney and his wife, 67-year-old Gladys G. Greeney and then took his own life.

The Sanger Police Department and Denton County Sheriff's Office were dispatched to a call Saturday evening at the 2500 block of Wichita Trail.

There are no other suspects involved in the investigation.