In Charleston, West Virginia, a woman fatally shot a man who opened fire on a throng of people with a semi-automatic rifle.

Dennis Butler, a 37-year-old with a long criminal background, was shot and died after he targeted a group of about 40 people at a birthday party.

The woman’s prompt action, according to police spokesman Tony Hazelett, saved lives and may have stopped a mass shooting.

It comes after a school massacre in Texas sparked a national debate about guns.

Butler had been through the neighborhood earlier in the evening on Wednesday when he was told to slow down because youngsters were playing.

He returned, armed with an AR-15-style weapon, and started fire on the birthday-graduation party outside the city apartment complex from the safety of his truck.

Mr. Hazelett told, “She’s just a member of the community who was carrying her weapon lawfully.”

He said. “And instead of running from the threat she engaged with the threat and saved several lives.”

After the incident, the woman stayed at the site and is cooperating with investigators.

According to authorities, no charges will be made against her.

Butler was found dead at the scene, with several gunshot wounds.

Butler obtained the handgun, which he was not legally allowed to carry as a convicted criminal, according to Hazelett.