Just before the opening bell at Henry Foss High School, prosecutors allege, Douglas Chanthabouly walked up to fellow student Samnang Kok in a hallway, said "What's up?" and fired a pistol into the 17-year-old's face.

When he was captured in a nearby neighborhood about two hours later, Chanthabouly allegedly confessed to the fatal shooting, according to court documents. But he refused to tell police why, saying "I don't want it in the news."

Chanthabouly, 18, pleaded not guilty Thursday to one count of first-degree murder for the Wednesday morning shooting. He was ordered held on $1 million bail.

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Asked after the hearing why her son might have killed Kok, Chantha Chanthabouly said: "I don't know. ... Only God can tell you."

A probable cause statement written by prosecutors said Chanthabouly told police he "did not know Mr. Kok, but knew of him."

Witnesses told police that Chanthabouly pointed a handgun at Kok and fired a shot into his face, prosecutors wrote. Police believe the shot was fired from no more than a foot away.

The shooter stood over the body and fired twice more, hitting Kok in the lower left side and left buttock, the statement said. The gunman then fled the building.

After the court hearing, which was attended by members of both families, Chanthabouly's family offered a tearful apology. Contrary to what authorities say Chanthabouly told them, his mother said the families did know each other, but did not say how. Both families are Cambodian.

"I love the family," Chantha Chanthabouly said, sobbing uncontrollably. "I love that boy, the boy that passed away, and the boy they have locked up is mine."

The school reopened Thursday with increased security. Police cruisers were in the parking lot, and officers patrolled the hallways.

Samnang Kok was the father of an 18-month-old boy, and had hoped to become a soldier after graduating, said his father, Rorth Kok.

"My son is gone and his baby is always crying after his father," the elder Kok said, breaking into sobs.