The woman opened her car door, stepping out into the pre-dawn darkness of the Harris County, Tex., Sheriff’s Office substation parking lot. She’d been up all night, arguing with her teenage son about what they were about to do. And here they were, watching as a deputy walked over to them to ask whether they needed help.

The mother spoke first: My son just killed a man, she told the deputy. I’m here to turn him in.

The deputy went over to the boy, officials told KHOU, and asked whether this was true.

“Yes,” the boy replied.

Then he got out of the car and put a handgun to his head. The deputy pulled out his own weapon, ordering the young man to drop the gun.

Instead, the boy pulled the trigger, firing a single bullet into his skull as the deputy and his own mother watched in horror. He was taken to the hospital in critical condition and later died.

Reports have conflicted about whether the boy is 17 or 18 years old.

The nightmare in Katy, Tex., just outside Houston, had begun hours earlier, when the teenager — who has not been identified — allegedly got into an argument with another man about a girl they were both dating, Harris County Sheriff’s Sgt. Cedrick Collier told the Associated Press.

Darian Mitchell, who is friends with the teenager, said the two were hanging out at his house when he got a call from his girlfriend.

“He was like, ‘What are y’all doing?’ and she said, ‘I’m cheating on you right now.’ He got so mad so he kept yelling. He told her and her boyfriend to come meet us, to talk,” Mitchell told KHOU. “I don’t know why he was tripping over this one girl, but it was not worth it.”

The woman and the other man, who friends identified as 25-year-old Army veteran James Ayala, drove up to Mitchell’s house just after midnight. There was an argument, then the teenager pulled out a gun, fatally shooting Ayala, Mitchell said.

Two men were seen fleeing the scene of the shooting in a white car, officials told the Houston Chronicle.

When the teenager’s mother found out what happened, she argued that he needed surrender to the police, according to the Chronicle. She drove him to the sheriff’s substation about 5:30 a.m. Sunday.

Then the unthinkable happened.

Collier told the Associated Press that the mother spoke to authorities after her son shot himself.

“She’s obviously destroyed because she just witnessed her son commit suicide in front of her,” he said.

The deputy who witnessed the shooting has been placed on administrative leave so he can “clear his head and make sure he’s OK” before returning to work, Collier added. The deputy did not fire his weapon during the incident.

The killing is still under investigation, the Chronicle reported.

Aaron Summerour, a neighbor of the teenager who killed himself, told KHOU that the boy went to nearby Morton Ranch High School. He had once been “mixed up with the wrong crowd,” the TV station reported, saying he was starting to turn his life around, citing neighbors of the teenager.

“He sounded like he was doing good. He had a job, he was getting his car. He had everything together and now that I hear this, it’s unreal, you know what I mean?” Summerour said.

Ayala, the 25-year-old victim, was a father of five and a “standout guy in the Army,” Jordan Downhour told the Houston Chronicle.

Downhour had been stationed with Ayala at Fort Stewart in Georgia. Ayala left the Army as a corporal E-4 a few years ago.

“He took me under his wing and picked me up in Brigade. He showed me all the ropes,” Downhour said. “… I wish he would’ve stayed in. I think this wouldn’t have happened.”

Ayala’s family members were reluctant to speak with KPRC, another local TV station — they were too distraught, reporter Bill Spencer said.

But one relative, recalling how Ayala had served in Iraq, said this: “It’s so sad and crazy that he risked his life all of that time defending our country, only to come back here and be murdered by some kid with a gun.”

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