RIESEL, Texas (CBSDFW.COM) – A teacher in Central Texas is charged with murder for allegedly shooting and killing her teenage son as she drove him to school in Riesel on Monday, Nov. 9.

Sarah Elizabeth Hunt, 39, encountered two people near the Riesel Square after the shooting and told them her son needed help and was “with her mother in heaven,” according to an affidavit released Tuesday and reported by Waco CBS affiliate KWTX reported.

“What have I done…this is not real,” she told the two people, the affidavit says.

Later, under questioning about what happened, “she would respond by sobbing, saying ‘I didn’t mean to, I didn’t mean to,’” the affidavit says.

Hunt is held in the McLennan County Jail with bond set at $500,000.

Sarah Elizabeth Hunt (credit: McLennan County Jail)

A passerby spotted Hunt’s white Hyundai minivan on a roadside just before 8:00 a.m. Monday and called Riesel police.

That’s where authorities found her son, Garrett Hunt, 17, dead of multiple gunshot wounds.

“When law enforcement found the vehicle, all the doors were closed, the windows were rolled up, and the vehicle was running,” the affidavit says.

Authorities found multiple .40 caliber cartridge cases on the ground on the driver’s side of the minivan and found a .40 caliber pistol inside the vehicle along with a spare magazine.

Hunt, the affidavit says, picked up her son from the camper in which he was staying with his father and was supposed to take him to school and drop him off, the affidavit says.

No one else was in the vehicle, the affidavit says.

The motive for the shooting is not yet known.

The family recently moved to the area, authorities said.

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