A gunman slaughtered seven people at a Texas football watch party Sunday night – before police responded and killed the alleged shooter.

Two other people were wounded when the unidentified gunman opened fire inside the party at a single-family home off Spring Creek Parkway in Plano, less than 20 minutes from Dallas, around 8 p.m., FOX4 reported. Witnesses said the group was watching the Dallas Cowboys season opener against the New York Giants.

“It sounded like an argument between a woman and a man and it got really loud…next thing you know all you heard was multiple rounds just going off,” Crystal Sugg, who works nearby, told FOX4.

Sugg said she heard a loud argument for about 20 minutes – and then gunshots.

“I heard guns and a lot of screaming,” she said. “All I heard was, ‘Boom, boom, boom, boom, boom.’”

The victims were not immediately identified. All of those killed and injured were believed to be adults

Other witnesses reported hearing about 30 or more gunshots.

“My neighbor had already heard the first couple of shots, and we came outside and next thing you know, all you heard was like, ‘pop, pop, pop, pop, pop, pop, pop, pop,’” Steven Featherland said.

Tilley said police initially responded to a report of shots fired. When the first officer arrived and went inside the home, the officer confronted the suspected shooter.

“After he heard the gunshots, he made entry and that’s when he observed several victims inside and then engaged the suspect,” police spokesman David Tilley said The Dallas Morning News.

Police have not released a motive for the shooting.

Tilley said a shooting of this magnitude was unusual for Plano, especially in such a quiet neighborhood. He could not say whether police had been called to the home before Sunday.

“I’ve been here all my life,” Tilley said. “I’ve never heard of anything like this.”

Sugg added: “I’m in shock. It is always quiet around here.”

The Associated Press contributed to this report.