A 16-year-old suspect armed with two knives allegedly went on a mass stabbing spree today at a Pennsylvania high school before he was tackled by the assistant principal, according to authorities.
Thomas Seefeld, the police chief in Murrysville, Pa., told reporters this morning that he did not know the motivation for the mass stabbing at Franklin Regional High School but that it could have been a lot worse if immediate action had not been taken.
The name of the 16-year-old suspect has not been released by police, however a student at the school told ABC News the person believed to be the alleged stabber seemed like a "pretty normal kid."
At least 20 people were injured after the stabbings inside the school at the start of the school day, emergency management officials said.
No fatalities were reported, Westmoreland County emergency management spokesman Dan Stevens said.
At least four people with injuries Stevens described as "serious" were flown to area hospitals for treatment. Others were not actually stabbed, he said, and some of their injuries were cuts and scrapes.
Among the victims of the stabbing was a security guard stabbed in the stomach, the police chief said.
Dr. Mark Rubino, chief medical officer at Forbes Hospital, said his team treated eight victims, three of whom he said had severe injuries.
"We were ready to handle what came in the door," Rubino said, adding that, at one point, 20 surgeons were in the emergency room.
Rubino said the injuries spanned from "relatively superficial wounds" to "severe injuries to abdominal injuries." He said almost all of the stab wounds appeared to follow a pattern and were inflicted on the victims' lower abdomens.
The breakdown of injured and whether they were students or staff was not immediately known, but Forbes and Allegheny General Hospital initially reported nine patients ranging in age from 15 to 60.
Alyssa Finch, who said she is a student at Franklin Regional High School, told ABC News a fellow student pulled the fire alarm during the stabbing "because he knew what was happening ... and he wanted the people to get out."
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A statement posted on the Franklin Regional School District's website said classes were cancelled today and that parents of middle school and high school students should report to Heritage Elementary for reunification. Any student who drove to school would not be released until a parent came to pick them up, the statement added.
Pennsylvania Gov. Tom Corbett said in a statement that he was "shocked and saddened" by the incident.
"As a parent and grandparent, I can think of nothing more distressing than senseless violence against children. My heart and prayers go out to all the victims and their families," Corbett said. "I have directed the Pennsylvania State Police to assist local law enforcement in its investigation in any way possible. Other state resources will be made available to the community, if needed. I assure the citizens of Murrysville that they have the full support of my administration."