Until Wednesday, the 16-year-old Pennsylvania boy who's charged with multiple counts of attempted murder and aggravated assault after a stabbing attack at his high school was known as "a nice young boy," his attorney said this morning. Now the sophomore is in custody after the attack that left more than 20 people — nearly all of them fellow students — injured.

On CNN's New Day, lawyer Patrick Thomassey said "nobody would expect this." The teenager, he said, "has never had any mental health problems whatsoever ... never been in the juvenile court system" and was a "well-liked student."

"He interacted well with other students," Thomassey said. "Obviously, there's a problem. ... You don't just leave and go to school and do what he did." The boy's parents, Thomassey added, "are horrified ... this is not their son."

As for the question on many minds — why? — Thomassey doesn't have an answer at this point. He met last evening with the teen, who is identified in court papers as Alex Hribal. But as for any reason for the attack, Thomassey said he's not aware of any as of now.

We followed the news of Wednesday's attack at Franklin Regional High School in Murrysville, Pa., in this post. The NPR news station in Pittsburgh, WESA, has collected its coverage here.

As of Thursday morning, the suspect is charged with four counts of attempted murder, 21 counts of aggravated assault and one count of possessing a weapon on school property. The teen is being charged as an adult, though Thomassey said he may petition to have the case moved to juvenile court.

The number of charges may change as the investigation into the attack continues. Reports about just how many people were injured also may change — and already have since last evening.

CBS Pittsburgh notes this morning that Westmoreland County (Pa.) officials now say there were at least 24 people hurt — "21 students stabbed, 1 security guard stabbed, and 2 others injured." That total is three more than were thought to have been injured as the day ended Wednesday.

More on the story:

-- "A witness says [the suspect] had a 'blank expression' on his face as he flailed away with two knives in the hallway just before the start of classes." ( WESA)

-- Four of the injured students "remained in critical condition Wednesday evening." ( Pittsburgh Post-Gazette)

-- "Doctors say they expect all the victims to survive, despite large and deep puncture wounds to the abdomen in some cases." (WESA)

-- Authorities say private security Sgt. John Resetar was the first adult to confront the attacker. He was stabbed in the abdomen. (Post-Gazette)

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