Gladden will be charged as an adult with attempted first-degree murder and assault according to Baltimore County police and court records. Authorities say the student opened fire Monday in the high school's cafeteria.
AP reports he allegedly fired two shots and wounded a 17-year-old classmate before being stopped by teachers. ABC News reports that several students who witnessed the shooting say that a school guidance counselor tackled Gladden after the first shot was fired and that a second shot was fired into the ceiling during the struggle.
The victim remained in critical condition at Maryland Shock Trauma Center on Tuesday, a hospital spokeswoman said.
Gladden's father was reached at home Monday evening and confirmed his son was the shooter. The father told an AP reporter that his son had been bullied but did not give further details.
A woman at the home gave a statement to AP. She said, "We are horrified. We did not see this coming and our thoughts and prayers are with the victim and the victim's family."
Tony Lyle, 15, a Perry Hall junior told the Baltimore Sun that he was close to Gladden and that he was a "normal kid," but in recent years had changed, growing out his hair and often keeping his head on his desk. "He didn't talk to no one," Lyle said Monday.
Baltimore County police reportedly searched a house and a shed that matched Gladden's address in court filings for more than an hour and a half. The Baltimore Sun reports that police could be seen removing some guns.