Alex Hribal, the student who allegedly waged a massive knife attack at a Pennsylvania high school on Wednesday, will be charged as an adult, CNN reported. The 16-year-old injured at least 22 people in the assault at Franklin Regional Senior High School in Murrysville, Pa.

ABC News revealed Hribal would be charged with four counts of attempted criminal homicide, 21 counts of aggravated assault and one count of possession of a weapon on school property. The suspect reportedly used two butcher knives to slash and stab fellow students during the assault, which occurred in the school's science wing before classes began.

Hribal’s motive is currently unclear, but his apparent Facebook page has references to Hitler, reported. A classmate told Pittsburgh Post-Gazette that Hribal was "sort of a shy person. To me he never seemed like someone who would do anything violent. He never seems very upset or anything of that."

The classmate said Hribal is "sort of nerdy, short.” The classmate added: "I would assume that he was bullied and there was a good amount of depression.” But the student said he never saw Hribal get picked on.

However, a different source told ABC News the sophomore “wasn’t a real well-liked kid.” The insider graduated from the school in 2010, but has a sister who is still a sophomore there.

“It was pretty common knowledge between all the kids that he had made some death threats,” the source said. “I guess the kids who got the threats just assumed it’s no big deal," he said, adding that his sister was “about a foot or two” from another student who was injured in Wednesday’ bloodshed.

“The kid in front of her started screaming and she saw a bunch of blood,” the source said, in reference to his sister’s story.

According to ABC News, Hribal is being held at a juvenile detention center in Westmoreland County and has been denied bail. His preliminary hearing was set for April 30.

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