Updated

A 15-year-old sophomore at a suburban Baltimore high school who made references to murder-suicide on Facebook has been charged as an adult in the shooting of a classmate on the first day of school, authorities said Tuesday.

Robert Wayne Gladden Jr. was being held without bail on charges of attempted first-degree murder and first-degree assault, Baltimore County police said. No court hearing has been scheduled and the state's attorney's office did not know if he had a lawyer. Police were planning a news conference later Tuesday.

Gladden's father told The Associated Press that his son had been bullied, although he did not provide details. The teen's last status update on his Facebook page, posted the morning of the shooting, read: "First day of school, last day of my life. ... f--- the world."

Gladden also referred to mass murderer Charles Manson and gave himself the nickname "SuicidalSmile." The page, identified by classmates as belonging to the suspected shooter, was just launched in July, and the three photos of Gladden all show his face hidden behind long, dark hair. He describes himself as a "metalhead" and a fan of musicians Marilyn Manson and Slipknot.

According to charging documents, Gladden walked into the cafeteria at Perry Hall High School Monday morning and fired a shot toward a lunch table. A 17-year-old classmate, Daniel Borowy, was struck in the back.

More On This...

Teachers and school staff then rushed toward the teen, and in the ensuing struggle, he fired another shot that hit the ceiling, investigators said in the documents. The staffers were able to get the gun away from him and he was arrested by a school resource officer.

Witnesses credited guidance counselor Jesse Wasmer with getting the gun away from Gladden.

The suspect's father, Robert W. Gladden, told the AP Monday evening that his son was the shooter and indicated his son had been bullied. He gave no further details.

A woman who was also at the home in Middle River and said she was related to the elder Gladden gave the following statement on the family's behalf: "We are horrified. We did not see this coming and our thoughts and prayers are with the victim and the victim's family."

Borowy remained in critical condition Tuesday morning at Maryland Shock Trauma Center, a hospital spokeswoman said.

Classes resumed Tuesday at the school amid a low-key police presence. About 150 students turned out for a prayer vigil organized by local churches on the school grounds.

Shane Boyer, 44, who was dropping off his 13-year-old daughter Corinne, said the vigil helped calm students still dealing with the shooting. Boyer said he knew immediately that his daughter was safe after the shooting because he received text messages from her. One read, "Someone just shot a gun in lunch," followed by another that said, "I ran out I am do (sic) scared there's helicopters + cops + we are all outside."