MURPHY, Texas (AP) -

Investigators are trying to determine whether a romantic dispute led to the slaying of a couple at a North Texas home and then his ex-girlfriend taking her own life in Dallas.

Police say the bodies of a man and his girlfriend were discovered Saturday morning in a home in Murphy, about 15 miles northeast of Dallas.

Murphy police identified those victims as 40-year-old Jonathon Masin, who lived at the residence, and 38-year-old Amy Picchiotti of Dallas.

Dallas police hours later located a woman's body in an SUV in an apparent suicide. Police say 45-year-old Michele Boyer formerly dated Masin.

Police say a handgun similar to a weapon believed to be have been used in the double slaying was found near Boyer.