Updated

Lewisville police say a gunman who fatally shot a relative then held off law officers for hours ended the standoff by killing himself.

The domestic dispute at a house ended around 2:30 a.m. Friday.

Capt. Jay Powell says the gunman Thursday night shot and killed a person believed to be either his son or his stepson. Powell says the gunman, who held law officers at bay for about seven hours, was discovered dead when police entered the house.

Police say the victim's mother witnessed the shooting of her son, then ran to a neighbor's home to seek help.

Police are trying to determine what prompted the deadly incident. Names of the pair who died were not immediately released.

Lewisville is about 10 miles northwest of Dallas.

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