PITTSBURGH, June 11 (Reuters) - A 16-year-old boy accused of stabbing 21 people at a Pittsburgh-area high school in April pleaded not guilty Wednesday to all charges, his lawyer said.
Alex Hribal of Murrysville, Pennsylvania, is being charged as an adult for an attack that left several Franklin Regional High School students in critical condition. Hribal is accused of entering the school wielding two kitchen knives, stabbing students and staff in his wake.
He is facing 21 counts of attempted homicide and other charges.
His lawyer, Patrick Thomassey, said he requested a jury trial but did not disclose a legal strategy.
"We are going to now proceed to the discovery process, where they are going to give me all the search reports and videos and we are going to figure out how we are going to defend it," he said.
A warrant unsealed Tuesday revealed Hribal wrote a note three days before the attacks in which he expressed his "dissatisfaction with school and society."
The document was discovered in his locker on the day of the stabbings and was titled "Ragnarok," in a possible reference to bloody Norse end-times mythology.
The warrant also revealed that two students received threatening phone calls the day before the attack, suspected to have been from Hribal.
An April affidavit also referenced a document Hribal wrote three days before the attack, but it was not known if it is the Norse-titled tract.
In the note he wrote: "I can't wait to see the priceless and helpless looks on the faces of the students of one of the 'best schools in Pennsylvania' (when they) realize their precious lives are going to be taken by the only one among them that isn't a plebeian."
The affidavit also stated that Hribal refused to let go of his knives after the vice principal grabbed him and students fled the hallways in panic. Hribal was quoted as saying: "No, I am not dropping them. My work is not done. I have more people to kill."
Hribal is currently being held without bail at a juvenile detention facility, Thomassey said. (Reporting by Elizabeth Daley; Editing by Edith Honan and Lisa Shumaker)