Houston authorities have charged a 48-year-old man with multiple counts of capital murder after deputies discovered the bodies of six children and two adults in a home where the man was arrested.

The man, David R. Conley, allegedly was involved in a standoff with deputies that ended when he was coaxed out of the home by hostage negotiators without incident, according to the Houston Chronicle.

Once deputies entered the residence, they discovered the gruesome scene.

“He restrained, shot and killed eight people,” Celeste Byrom, an assistant district attorney, said during a court hearing Sunday in which Conley was ordered held without bail, according to the Chronicle.

Byrom said Conley gained access to the home through an unlocked window and restrained his victims using handcuffs before shooting them in the back of the head, according to CBS affiliate KHOU.

Thomas Gilliland, a spokesman for the Harris County Sheriff’s Office, told the Chronicle that the relationship between Conley and the victims — who ranged in age from 6 to 50 — remains unclear. The Chronicle identified the victims as Valerie Jackson, 40, her husband, Dwayne Jackson, 50, and six children: Jonah, 6, Trinity, 7, Caleb, 9, Dwayne Jr., 10, Honesty, 11, and Nathaniel, 13. The Associated Press reported that Nathaniel was believed to be Conley’s son with Valerie Jackson. Police had earlier described the victims as five children and three adults, and earlier reports had put Conley’s age at 49.

At a news conference Sunday afternoon, Chief Deputy Tim Cannon said the degree of violence was difficult to fathom, according to KHOU.

“We’re here today on a very sad day,” Cannon said. “We’re here with our brothers in arms standing behind us because we’re all hurting. It’s a difficult day for us at the sheriff’s office. Once again, a tragedy has struck . . . our city. Our hearts go out to those . . . affected by this tragedy.”

The incident began when authorities arrived at the home around 9 p.m. Saturday to perform a welfare check, KHOU reported. When nobody answered the door and authorities learned that Conley was inside and wanted on a warrant for aggravated assault of a family member, deputies surrounded the home.

Gilliland told CNN that deputies surrounding the home decided to enter when a child’s body was spotted through a window.

Conley allegedly began firing a weapon inside the residence, forcing the deputies to pull back and call in a high-risk operations unit, similar to a SWAT unit, and hostage negotiators to the site.

Texas police say an alleged shooter surrendered after a brief standoff, and that five children and three adults were later found dead in a Houston home. (Reuters)

Gilliland told CNN that, after more than an hour, negotiators persuaded Conley to surrender and that he was arrested without further incident.

The spokesman told the Chronicle that investigators want to know “who belongs in the house . . . who was supposed to be there and who was not.” He noted that authorities had been called to the residence before, but the nature of the calls was not known.

The Chronicle reported that Conley had a history of violent behavior that had landed him behind bars as recently as last month, when he allegedly attacked the woman he was dating — Valerie Jackson — by slamming her head into a refrigerator:

The July attack began after Jacksons’ 10-year-old son came in from the park after dark. Conley allegedly told her, “that if she did not discipline her son, he was going to do it himself,” court records state. He then allegedly grabbed a belt, but Jackson took it from his hands. In the resulting scuffle, Conley pushed her head into the refrigerator multiple times.

In 2013 he was convicted of assaulting Jackson, and got nine months in jail. In that case, she received an emergency protective order prohibiting Conley from contacting her.

Conley also has a prior conviction in 2002 for felony retaliation and in 1994 for possession of a controlled substance, among many other charges.

“Everybody’s shocked and everybody’s hurt,” a teacher from a nearby elementary school who knew the children told the Chronicle. “They’re good kids, very good kids. And so helpful. Very helpful. They’re always sweet kids. I don’t have anything negative to say about that family.”

Gilliland said counselors from the sheriff’s office were being sent to the residence to help deputies personally process the crime scene. Because of the number of victims, Gilliland said, investigators “will be here for quite a while,” according to NBC News.

“It’s hard job being a patrolman in this town,” Gilliland told the Chronicle. “Our deputies do a yeoman’s job every day. But when they are forced to see some of the most horrific things along this nature, especially of children, and someone so callous to do something like this to children, we have our family assistance coming out to talk to our deputies and help them decompress.”

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