A man shot and killed four children and two adults -- at least some of whom might have been his estranged wife's relatives -- at a Houston-area home Wednesday, authorities said.
A seventh person, a 15-year-old girl, was critically wounded at the home in Spring, Texas, and taken to a local hospital.
Ron Lee Haskell was arrested after a three-hour standoff that followed a short chase with sheriff's deputies. Haskell, 34, is being held on charges of capital murder, Harris County Precinct 4 Constable Ron Hickman said.
"I've not personally in 40 years seen a tragedy in one family that's this horrific," Hickman told reporters Thursday morning.
Officials: Suspect was prepared to take more lives
Haskell, apparently posing as a delivery driver late Wednesday afternoon, entered the home of one of his estranged wife's relatives while only the children were there, Hickman said.
Wearing a purple "Fed-Ex-looking shirt," the suspect "gathered up the children" and waited for the two adults to arrive, Hickman said.
The slain children were two boys, ages 13 and 4, and two girls, ages 9 and 7. The adults who were fatally shot were a 39-year-old man and a 33-year-old woman.
Haskell might have been an uncle to at least some of the children, but his relationship to everyone in the home wasn't immediately clear, Hickman said. Haskell was not the slain children's father, as police had mistakenly asserted earlier, Hickman said.
Investigators didn't immediately know what led to the shooting; Hickman described it as a "domestic situation."
Hickman said he didn't know Haskell's occupation.
Authorities believe the suspect was prepared to take the lives of other relatives who lived nearby.
As the gunman left, one of the victims called police and notified "us of the location that she believed that he may go from there," Hickman said.
"Grandparents were also targets of him," Harris County Sheriff's Sgt. Thomas Gilliland said. "Fortunately, they were brought out of the house before that could happen, [or] we would have had more tragedy."
Haskell approached the second home and saw officers there; he drove away and the officers pursued him, Hickman said.
Police trapped Haskell in a cul-de-sac, and he surrendered after about three hours, having had discussions with negotiators, Hickman and Gilliand said.
During much of the standoff, Haskell held a gun to his head, while deputies surrounded him with their weapons drawn, police said.
Haskell has children with his estranged wife, but those children were not believed to have been in the Spring home where the shootings happened, Hickman said. The estranged wife lives out of state, police said.
Spring is about 20 miles north of Houston.
-- CNN's Dave Alsup and John Branch contributed to this report.
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