MURRYSVILLE, Pa. - A 16-year-old boy described as quiet and shy flailed away with two knives in the crowded halls of his suburban Pittsburgh high school Wednesday, stabbing and slashing 21 students and a school police officer before an assistant principal tackled him, authorities said.
At least four students were in critical condition Wednesday evening, including a boy who was on a ventilator after a knife pierced his liver, missing his heart and aorta by only millimeters, doctors said.
The suspect, identified as Alex Hribal, a sophomore at the high school, was taken into custody and treated for a minor hand wound.Witnesses said he maintained a "blank expression" during the attack.
Hribal was charged as an adult on Wednesday with four counts of attempted homicide and 21 counts of aggravated assault. He was shackled by his hands and feet and was dressed in a hospital gown in his appearance before a magisterial district
The rampage - which came after years in which U.S. schools have geared much of their emergency planning toward mass shootings, not stabbings - set off a screaming stampede, left blood on the floor and walls, and brought teachers rushing to help the victims.
Investigators have not determined a motive, but Murrysville Police Chief Thomas Seefeld said they were looking into reports of a threatening phone call between the teenager and another student the night before, CBS Pittsburgh reported. Seefeld didn't specify whether the boy reportedly received or made the call.
The attack unfolded just minutes before the start of classes at 1,200-student Franklin Regional High School, 15 miles east of Pittsburgh. Police said it was over in just minutes.
Student Mia Meixner said the initial assault touched off a "stampede of kids" yelling, "Run! Get out of here! Someone has a knife!"
Witnesses said the attacker at first tackled a freshman and stabbed him in the belly, then got up and ran wildly down the hall, slashing other students. The knives were as long as 10 inches, authorities said.
Nate Moore, 15, said he saw the first attack and was going to try to break it up when the teenager got up and slashed his face, requiring 11 stitches.
"It was really fast. It felt like he hit me with a wet rag because I felt the blood splash on my face. It spurted up on my forehead," he said.
"I can tell you what we saw when we got there was the hallway that was pretty much in chaos as you can imagine, a lot of evidence of blood on the floors in the hallway.We had students running about trying to get out of the area."
- Police Chief Thomas Seeield
Michael Float, 18, said he had just gotten to school when he saw "blood all over the floor" and smeared on the wall near the main entrance. Then he saw a wounded student.
"He had his shirt pulled up and he was screaming, 'Help! Help!'" Float said. "He had a stab wound right at the top right of his stomach, blood pouring down." Float said he saw a teacher applying pressure to the wound of another student.
Moore and 16-year-old Mia Meixner called Hribal a shy boy who largely kept to himself, but they said he was not an outcast and they saw no indication he might be violent.
"He was never mean to anyone, and I never saw people be mean to him," Meixner said. "I never saw him with a particular group of friends."
Hribel was a sophomore at Franklin Regional, where he didn't especially stand out. Schoolmates said he was quiet but not an outcast.
Witnesses said the teen had a "blank expression" on his face as he jabbed at student with the knives. Nate Moore, 15, said he saw the suspect tackle and stab a freshman before the attacker got up and slashed Moore's face.
The attacker "had the same expression on his face that he has every day, which was the freakiest part," said Moore, who required 11 stitches to close his wounds.
"He wasn't saying anything. He didn't have any anger on his face. It was just a blank expression."
Meixner said the suspect had a "blank look" during the rampage.
"He was just kind of looking like he always does, not smiling, not scowling or frowning," she said.
Hribel lives in a colonial home on Sunflower Court in Murrysville with his parents and a brother who is a junior at the high school, CBS Pittsburgh said. Police were keeping reporters at a distance from the house on Wednesday evening as investigators searched the boy's computers.
Neighbors said they were stunned by the boy's arrest in the rampage.
"I'm just in shock," neighbor Lori Renda told the station. "I have no idea what could have caused it at all." "We've known them since we moved in. It's tragic," said Terri Ledonne, another neighbor
Pennsylvania Gov. Tom Corbett praised the reaction of the students and staff at the school.
"There are a number of heroes in this day," he said.
Gov. Corbett commended students who remained with their friends, teachers and other staff who pulled students out of hallways to safety, cafeteria workers who cared for wounded students and an assistant principal, Sam King, credited with subduing the assailant.
A local hospital said that one student applied pressure to an injured classmate, possibly saving the student's life.
A student, Ian Griffith, said he saw the school police officer confront the student, who then stabbed the officer. King then tackled the boy, Griffith told the Pittsburgh Tribune-Review.
King's son told The Associated Press that his father was treated at a hospital, though authorities have said he was not wounded by the knife.
"He says he's OK. He's a tough cookie and sometimes hides things, but I believe he's OK," Zack King said. The son added: "I'm proud of him."
King lives just up the street from Hribal's family. The police chief called Sam King's actions admirable.
Someone, possibly a student, pulled a fire alarm after seeing some of the stabbings, the police chief said. Although that created chaos, Seefeld said, it emptied out the school more quickly, and "that was a good thing that that was done."
Several students told CBS Pittsburgh the person who pulled the fire alarm was student Nate Scimio (pictured L in a selfie via Instagram )
Also, a girl with "an amazing amount of composure" applied pressure to a schoolmate's wounds and probably kept the victim from bleeding to death, said Dr. Mark Rubino at Forbes Regional Medical Center.
Public safety and school officials said an emergency plan worked as well as could be expected. The district conducted an emergency exercise three months ago and a full-scale drill about a year ago.
"We haven't lost a life and I think that's what we have to keep in mind," said county public safety spokesman Dan Stevens.