CALLAHAN, Fla. – A 36-year-old Nassau County man shot and killed his aunt during an argument over a parking space Thursday night and then killed himself, deputies said Friday.

According to the Nassau County Sheriff's Office, the murder-suicide was reported about 7 p.m. at a home on Swallowfork Avenue in Callahan.

Deputies said James Aaron Proffitt got involved in an argument between his mother and his aunt, 55-year-old Melinda Sue Lein, got a handgun from his room, shot Lein and then shot himself.

Nassau County Sheriff Bill Leeper said Proffitt had been living with his mother, his aunt and his siblings in his mother's Callahan home.

"They are shocked that something like this would happen. (They) never thought it would. Certainly, they are upset," Leeper said. "They are all being cooperative. We don't know what made him snap to do that, but it's something that, unfortunately, occurred."

A neighbor who did not wish to be identified told News4Jax Friday that she's known the family for more than a decade and can't believe what happened.

"It doesn't make sense when things like this happen. But you never know what's going through someone's mind when they decide to do something like this," she said.

Proffitt has no criminal history and authorities have never been called to the home before, according to the Sheriff's Office.