A winning scratch-off lottery ticket worth $500 prompted an argument between a couple in their Fort Worth, Texas, home that ended with both dying of gunshot wounds, officials said on Tuesday.

Fort Worth police said Terry Martin shot his long-time girlfriend, Laurice Hampton, and then shot himself early on Saturday morning in the master bedroom of the house they had shared for several years.

The Tarrant County Medical Examiner's office ruled on Tuesday that Martin had committed suicide and that Hampton's death was a homicide.

Martin, 46, was found dead when officers arrived at the home about 6:30 a.m. on Saturday. Hampton, 48, was critically injured with multiple gunshots but was able to call 911 for help, police said.

Hampton was taken to a local hospital, where she died, police said.

"They were having an argument over a scratch-off lottery ticket winnings," said sergeant Joe Loughman. "We have been told they had a very volatile relationship."

Hampton told officers before she died that Martin had shot her and then shot himself.

Martin died of a gunshot wound to the head, according to the medical examiner.

Thanks to hearsetrax for the tip.