Local media reports the incident occurred during a Dallas Cowboys viewing party at a residential property.
At least eight people are dead, including the suspect, after a shooting at a home in Plano, Texas, authorities in North Texas said.
The shooting occurred around 8 pm Sunday in the city less than 32.2 kilometres (20 miles) northeast of Dallas.
Plano police spokesman David 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.
Tilley said the officer opened fire, killing the suspect.
According to gun.laws.com, Texas is one of the six states that bans the open carrying of handguns in the country. However, this is the only real restriction concerning firearms by Texas gun laws.
For the purchase of shotguns, rifles or any other firearm, no permission is required. One just needs to be at least 18 years of age and a resident of the state to acquire one.
BREAKING: Plano PD confirms 8 dead, 2 others in hospital after shooting at home on Spring Creek near Blue Ridge Trl- all adults I'm told pic.twitter.com/LfHvzNyRWf— David Goins (@dgoins) September 11, 2017
Dallas Cowboys viewing party
The shooting occurred at a Dallas Cowboys viewing party, local media reported.
A woman who lives near the house says she'd earlier seen people laughing and grilling outside.
Stacey Glover told The Dallas Morning News that the party started early Sunday afternoon. Then, she says, she heard shots around 8:00 pm. She opened her door and smelt gunpowder. She heard police who arrived yell "hands up" before more shots rang out.
Two others were injured in the shooting. Details about their condition were not released.
The victims and suspect have not been identified. All of those killed and injured were believed to be adults.
Police also have not determined a motive for the shooting. Additional details were not immediately available.
Tilley said that a shooting of this magnitude was unusual for Plano, especially in such a quiet neighbourhood. He could not say whether police had been called to the home before Sunday's incident.
A police investigation is ongoing.