MURRYSVILLE (KDKA/AP) -- Franklin Regional High School in Murrysville remained under police guard Wednesday night as investigators still consider the school a crime scene.
Twenty-four people were hurt at the school earlier in the day when police say 16-year-old Alex Hribal, a sophomore, went on a stabbing and slashing spree.
KDKA's Ralph Iannotti Reports:
The attack unfolded just minutes before the start of classes at the 1,200-student high school. Police said it was over in just minutes.
Witnesses said the boy with the knives at first tackled a freshman and stabbed him in the belly, then got up and ran wildly down the hall, slashing other students.
The attacker "had the same expression on his face that he has every day, which was the freakiest part," 15-year-old Nate Moore said. "He wasn't saying anything. He didn't have any anger on his face. It was just a blank expression."
Twenty-one students and a school security officer are being treated for knife wounds. Two other students were hurt in the chaos that followed.
Hribal appeared before a district judge in Export Wednesday evening.
He is being charged as an adult, and faces four counts of attempted homicide and 21 other counts.
KDKA's Mary Robb Jackson Reports:
He was denied bail after District Attorney John Peck described him as a threat to the community.
He was in a hospital gown when he appeared in court because after he was taken into custody this morning, Hribal was treated at a hospital for knife wounds to his hands.
As he was in court, a special team of FBI investigators was at his home where they confiscated his computer, and agents were seen carrying other possible evidence out of the home.
His lawyer, Pat Tomassey, described Hribel as "a nice young man who has never been in trouble before."
Tomassey said the family was "an Ozzie and Harriet-type family, and the boy's parents did not see this coming."
But what could cause it? What could trigger it? Those are the questions reverberating around Hribal's neighborhood following this morning's incident.
"I have no idea; I'm just in shock," said Lori Renda, a neighbor. "I have no idea what could have caused it at all."
Hribal is being described in his neighborhood as a shy boy.
"We've know them since we moved in. It's… it's tragic," said Terri Ledonne, another neighbor.
He lives in a colonial home on Sunflower Court with his parents and brother, Ryan, who is a junior. Police were keeping reporters at a distance earlier in the day.
Most of the families living on this cul-de-sac have children at the school.
"It's absolutely terrifying," said Sonya Kukalis, a neighbor. "It put you, obviously, in a panic mode and stuff until you know your children are okay and everything."
KDKA's Mary Robb Jackson Reports:
The high school will be closed for the next few days. The motive remains under investigation.
Murrysville Police Chief Thomas Seefeld said investigators were looking into reports of a threatening phone call between the suspect and another student the night before. Seefeld didn't specify whether the suspect received or made the call.
District Attorney Peck said, "We've only scratched the surface of the investigation into why this happened."
Doctors said they expected all the victims to survive, despite large and deep puncture wounds to the abdomen in some cases. The wounded campus police officer was released.
20 Injured In Stabbing At Franklin Regional High School (4/9/14)
More Reports by Mary Robb Jackson
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