Updated 8:19 p.m.

The teen suspect in a deadly shooting massacre that the county prosecutor said was “absolutely premeditated” was arraigned Wednesday on multiple charges in the attack and the deaths of four students he is accused of fatally shooting.

As the Detroit Free Press reports, 14-year-old Hana St. Juliana, 16-year-old Tate Myre; Madisyn Baldwin, and Justin Shilling, both 17, were killed in the school shooting. Juliana, Baldwin, and Myre died on Tuesday, and Shilling died on Wednesday. A teacher and six other students were injured.

Oakland County Prosecutor Karen McDonald had announced earlier Wednesday that Crumbley would be tried as an adult, citing “mountains” of digital evidence that the massacre was premeditated. Crumbley is facing numerous charges: Four counts of first-degree murder, one charge of terrorism causing death. If convicted of even some of the charges, he will face life in prison.

At the arraignment, Oakland County Sheriff Lt. Tim Willis spoke of a video Crumbley is believed to have made the night before the massacre, and said investigators also found a journal. According to the Detroit Free Press, Willis said that in one of multiple videos recovered from Crumbley’s phone, the suspect “talked about shooting and killing students the next day at Oxford High School. Further, a journal was recovered from Ethan’s backpack also detailing his desire to shoot up a school to include murdering students.”

The massacre was caught on the school’s surveillance video. Assistant Prosecutor Marc Keast said at the arraignment that the video shows Crumbley entering a bathroom with a backpack at 12:51 p.m. He then emerged without the backpack, but with a gun.

“At that point, he methodically and deliberately walked down a hallway, aiming the firearm at students and firing,” he said. “After children started running away from the defendant, he continued down the hallway again at a deliberate and methodical pace, pointing and aiming inside classrooms and at students who hadn’t had the opportunity to escape.”

As previously reported, deputies arrived within five minutes. Keast reportedly said that Crumbley then put the gun down and put his hands up.

“What’s depicted on that video, honestly, judge, I don’t have the words to describe how horrific that was,” Keast said, according to the Detroit Free Press.

Crumbley is behind held without bail.

Correction: An earlier version of this story mistakenly stated the days that Justin Shilling and Tate Myer died. Myer died on Tuesday and Shilling died on Wednesday.

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