A 17-year-old student is the fourth victim to die in a shooting at Oxford High School in Michigan as murder charges were announced against the teenage suspect.
The suspected shooter, Ethan Crumbley, 15, was charged Wednesday with four counts of first-degree murder, one count of terrorism causing death, seven counts of assault with intent to murder, and 12 counts of possession of a firearm in the commission of a felony.
He's being charged as an adult and will be arraigned later Wednesday afternoon, Oakland County Prosecutor Karen McDonald said at a news conference.
McDonald said that Tuesday's shooting at Oxford High School was "not just an impulsive act" and was planned.
"There is a mountain of digital evidence — videotape, social media, all digital evidence possible … and it absolutely, we are confident that we can show it was premeditation," she told reporters.
The charges came shortly after authorities announced that a fourth victim had died — 17-year-old student Justin Shilling.
Shilling died around 10:45 a.m. Wednesday at McLaren Oakland Hospital in Pontiac, according to the Oakland County Sheriff's Office.
Authorities previously identified the three other students who were killed as Hana St. Juliana, 14; Madisyn Baldwin, 17; and Tate Myre, 16.
Seven others were seriously wounded, including a teacher, and taken to hospitals, Sheriff Michael Bouchard said.
The shooting happened just before 1 p.m. Authorities said more than a hundred 911 calls came in to dispatch.
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Oakland County Undersheriff Michael McCabe said deputies responded to the shooting "and within five minutes had the suspect in custody."
During Wednesday's press conference, McDonald talked about how students, teachers and staff had to seek shelter as shots rang out.
"When the shooting started yesterday, the students and teachers and staff in the school had to act quickly to save their own lives," she said.
"Law enforcement and all of the first responders had to act quickly to prevent more lives from being lost and get help for those who had been shot."
The prosecutor said Crumbley was being charged with terrorism because of the people who had to flee and hide.
"What about all the other children who ran, screaming, hiding under desks? What about all the children at home right now who can't eat and can't sleep and can't imagine a world where they can ever step foot back in that school. Those are victims too and so are their families and so is the community. And the charge of terrorism reflects that," she said.
Authorities have not said what they believe led to the shooting, and McCabe said the suspect "invoked his right to not speak."
The handgun believed to have been used was recovered. Investigators believe the suspect's father bought the 9 mm Sig Sauer handgun on Friday, Sheriff Michael Bouchard said.
Prosecutors considering charges against suspect's parents
McDonald said they are considering charges against the suspect's parents.
The handgun authorities believe the suspect used in the shooting was purchased by the suspect's father days ago, the sheriff said Tuesday.
Bouchard said on CNN Wednesday morning that it's clear the suspect "came out with the intent to kill people."
"He was shooting people at close range, oftentimes towards the head or chest," he said. "It's just absolutely cold-hearted murderous. And our forensic team was working all night and so far I believe they recovered over 30 shell casings. So, we believe he fired at least 30 shots."
Bouchard said the suspect's parents have asked for a lawyer, and under Michigan law authorities cannot speak with a juvenile without parental permission.
"They have refused that permission," the sheriff said. "So, we can't get the motive from the suspect that we have in custody, but we think we've got a path to get a lot of supportive information as to how and why this occurred."