Douglas County Sheriff John Hanlin said in a press conference that the medical examiner had ruled Chris Harper Mercer’s death a suicide, but that the Oregon State Police are investigating it as officer-involved shooting.
Three cops were on the scene, including two Roseburg police department officers and one Oregon state trooper, Hanlin said. Gunfire was exchanged, but ultimately, Mercer took his own life, Hanlin said.
Douglas County District Attorney Rick Wesenberg said the investigation is near its conclusion and he expects to be presented with the case early next week. He also told press that he will do a thorough review before determining whether use of force was justified.
Stephanie Salas, the mother of victim Rand McGowan, told PEOPLE that her son, who was shot in the hand but survived the shooting, saw Mercer, 26, kill himself in a UCC classroom.
“Rand’s head was down, but he did say, ‘You come here. I want you to live.’ He wanted the person he chose to give the police something,” Salas says. “I don’t know what it was. It was information.”
McGowan, who was released from Mercy Hospital on Friday, told Salas that the students saw Mercer’s body after his death.
“Then he killed himself in the classroom,” Salas tells PEOPLE. “All the students were like, ‘Is he dead? Is he gone?’ Then they stood up and he said he saw the killer with a big hole in his head.”
Hanlin said that over 45 fire and EMS responders, five chief officers, four fire engine companies and 10 paramedic ambulances responded to the incident.
Nine victims were killed and nine more wounded in the attack.
A source familiar with the investigation told PEOPLE that the shooter was obsessed with Satan and documented his devotion to darkness in a manifesto recovered from his computer.
“The guy did this strictly for satanic purposes,” the source told PEOPLE. “He did it to become a god in hell. He wants to be evil. That is his goal, to serve Satan.”
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