(CNN) -- The peace of mind Paula Fisher sought for herself and her children when she left Pittsburgh nearly two decades ago was shattered outside Franklin Regional Middle School on Wednesday morning. "It was total chaos," Fisher said. "The kids weren't sure if they were supposed to stay in school or leave. They weren't letting anybody in and told us to stay back. There were ambulances running past us. I was able to see a lot of the parents that I know who have children in the high school." The middle school sits across a field from the Pennsylvania high school where a stabbing spree injured 21 people, authorities said. A suspect, 16-year-old sophomore Alex Hribal, was taken into custody and arraigned Wednesday afternoon on charges of attempted homicide.
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Stabbing spree at Pennsylvania high school injures 20 students
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Mother of middle school student says "It was total chaos"
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Murrysville, with a population of about 20,000, is a quiet residential enclave
"It was very shocking," said Fisher, who has lived in @placeholder 19 years.