What started out as a normal Wednesday morning at Franklin Regional High School in Murrysville, Penn. quickly erupted into a blood bath brought on by 16-year-old Alex Hribal.

Hribal's unexpected attack unfolded right before the start of classes at the 1,200-student high school. It lasted only five minutes, but during that short span of time, the violent teen managed to slash and stab twenty students and one security officer.

Before Hribal had the chance to create further damage, assistant Principal Sam King was able to disarm the boy of the two knives that he carried. Soon after, he was taken into custody, treated for a minor hand wound, and then brought into court in handcuffs, shackles, and a hospital gown. Hribal was later charged with four counts of attempted homicide, 21 counts of aggravated assault, and one count of possession of a weapon on school grounds.

Authorities have said that he would be prosecuted as an adult and he is currently being held without bail at Westmoreland County Regional Youth Services Center.

Penn Live reports that doctors expect all the victims to survive, despite deep abdominal puncture wounds in some cases.

As for the assistant principal who saved the day, it is reported that he did not suffer any knife wounds.

Little is known about Hribal's motive on the day of the stabbing. According to students, Hribal was never violent and quite friendly.

"From past experiences with him, he hasn't been violent at all. He's actually been a really nice kid from all the times I've talked to him. He was just more of a shy kid, and kept to himself," said Franklin Regional student Mia Meixner to CNN. "He was nice whenever you would talk to him. I never thought anything bad would happen with him."

According to CNN, FBI agents seized Hribal's personal computer in hopes of discovering a possible motive.

Hribal's attorney, Patrick Thomassey stated that the boy's parents, "...offer their condolences to everybody involved in this case. They're very upset. They did not foresee this coming at all. This is a nice young man. He's never been in trouble."