A sophomore student is accused of committing the crime.
It happened quickly. Officials say 21 students and a security guard were stabbed in a matter of about 5 minutes.
Police say the quick thinking of students and action taken by assistant principal Sam King stopped it from being even worse.
16 year old Alex Hribal will be charged as an adult in the stabbings.
Police say he used two knives about 8-10 inches long.
They did not confirm exactly what his motive was.
Three of the victims remain in critical condition, but all are expected to survive.
Law enforcement officials expect the investigation to take quite some time.
The high school will be closed for at least the remainder of the week. The middle school and elementary will open as normal
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