Police in Pennsylvania have identified and charged a 16-year-old boy accused of stabbing and slashing 20 fellow students and a security guard at a high school.
Authorities say Alex Hribal was being charged as an adult with four counts of attempted homicide and 21 counts of aggravated assault following the Wednesday morning attack in Murrysville, 24 kilometers east of Pittsburgh.
Officials say Hribal, armed with two knives, went on the rampage just minutes before the start of classes at 1,200-student Franklin Regional High School. An assistant principal finally tackled the boy and disarmed him. They also say a police officer handcuffed the suspect.
A hospital spokesman says four victims appear to have life-threatening injuries, but are expected to survive. Seven victims are listed in serious condition with wounds to their torso, abdomen, chest or back.