ODESSA, TX (KWES) - UPDATE: Authorities released the booking photo for James Gabriel McDonald, 17, Thursday morning and confirmed the investigation into Wednesday's deadly shooting is ongoing.
James Gabriel "Gabe" McDonald, 17, confessed during a police interview to shooting his mother and father with a Taurus 9 mm handgun while they slept, according to the arrest affidavit.
Authorities said officers were dispatched to 5304 Conley Ave around 5 a.m. and found Gregg McDonald and his wife, Jana McDonald, both 52, dead.
They had each sustained a single close-range gunshot wound, according to sources close to the investigation.
"Definitely a tragic situation," said Cpl. Steve LeSueur, a spokesman for the Odessa Police Department. "Investigation revealed [Gabe] McDonald shot and killed both of his parents... He was immediately taken into custody."
Investigators confirmed a fourth person, Gabe's older sister, was also in the house during the shooting.
"Grace McDonald [the suspect's sister] advised that [Gabe] had come into her room and told her he was going to shoot their parents," the affidavit states.
Grace advised she "thought he was kidding," according to the document, and heard the two gunshots that killed her parents "moments later."
Authorities could not confirm if her brother had made similar statements to her in the past.
"The McDonald family is standing behind Gabe," said Justin Low, the teenager's defense attorney. "Relatives say this is completely out of character and he appeared fine earlier in the evening."
He declined to release information relating to the murder suspect's mental health.
A longtime neighbor, Connie Williams, said she "watched him grow up" and described him as a "typical American boy."
Gabe McDonald cannot be sentenced to death, despite being charged with capital murder, due to his age, according to Low.