Police said nine people in all were shot. Seven died at the scene, while two were transported to the hospital. The eighth victim died while in surgery.
Investigators said the shooter is known by the people who were inside the home, and there are no other suspects. The shooter is among the dead, police said.
We do not yet know the names of the suspect or the victims. All of those killed and injured are believed to be adults.
The victims had gathered for a cookout at the house before the game began, and at some point, the suspect opened fire both inside and outside the house.
The bodies of the gunshot victims were found strewn about the house. Police also recovered multiple firearms at the scene.
An eyewitness told local media that she heard as many as 40 gunshots coming from the home.
Plano police spokesman David 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.
The Associated Press contributed to this report.
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