TJ Lane has been identified as the teenage killer who shot two students dead at Chardon High School in Ohio and left another three injured.
The teenager left a chilling note on his Facebook page weeks before the shooting.
TJ Lane, 17, who classmates described as a bullied outcast, ranted about "a man with a frown. No job. No family. No crown. His luck had run out. Lost and alone".
Local reports identified one of the other shooting victims as Russell King Jr., a sociable 17-year-old who had started dating an ex-girlfriend of the shooter.
After being shot in the back while sitting at a table in the cafeteria, Russell King Jr. was airlifted to MetroHealth Medical Center.
The Center identified the fatally slain student as 16-year-old Daniel Parmertor, who was shot when TJ Lane allegedly targeted a group in the high school cafeteria at Chardon High School.
In the wake of the shooting, other students have said that TJ Lane was known as an outcast who had apparently been bullied. He had Tweeted that he would bring a gun to school, but nobody took the threat seriously.
Now investigators hope to gain some insight into the mind of the killer, and have found a chilling note he wrote about his dark thoughts two months before the shooting spree.
Freshman Danny Komertz, 15, said he was just about to leave for his first-period health class when he heard a loud popping sound and then saw the gunman open fire.
The freshman said that the person who died was trying to get under a cafeteria table to protect himself and shield his face.
Danny Komertz says that there were at least 100 students in the cafeteria at the time and that most fled immediately as shots were fired.
"He was aiming right at them as he was two feet away … He wasn't shooting around the cafeteria at all. He was directly aiming at the four of them," the student said.
Another student, Danny Mueller, saw the entire incident because he was right in the middle of it, so much so that his ear was grazed by a bullet.
"All of a sudden we heard a loud bang, almost like a firework. We turned around and I saw T.J. standing at the table behind us with his gun pointed and firing," he said.
"His first shot made me look. His second shot I watched him take, which hit somebody behind me, and his third shot hit me as I was turning away.
The shooting ended when the school's assistant football coach Frank Hall chased TJ Lane out of the building, with many saying that the heroic move is just in keeping with the coach's nature.
"Coach Hall, he always talks about how much he cares about us students, his team and everyone. And I think today he really went out and he proved how much he cared about us. He would take a bullet for us," said student Neil Thomas.
The first victim's family issued the following statement through the hospital : "We are shocked by this senseless tragedy.
Daniel Parmertor had aspired to be a computer repairman, according to AP, and was shot while waiting for the bus bound for a vocational centre.
His teacher at Auburn Career School had no idea why Daniel Parmertor, "a very good young man, very quiet", had been targeted, said Auburn superintendent Maggie Lynch.
Reports on TJ Lane's personality and social status have been shaky, as each student interviewed paints a different picture of the alleged shooter.
Some say he was a loner, others say he was bullied, and yet another said TJ Lane was "gothic".
By midday, officers investigating the shooting blocked off a road in a heavily wooded area several miles from the school. Federal agents patrolled the muddy driveway leading to several spacious homes and ponds, while other officers walked a snowy hillside.
There are mixed reports as to whether TJ Lane was enrolled at Chardon High School or whether he was just there while waiting to be transferred to Lake Academy Alternative School.
On their website, Chardon High School says that it handles students with a variety of issues, including "substance abuse /chemical dependency, anger issues, mental health issues, truancy, delinquency, difficulties with attention/organization, and academic deficiencies".
According to Superintendent Maggie Lynch, the two males shot were both 17, and a third was 16.
A spokesman confirmed that one of the 17-year-old boys and an 18-year-old girl were both in stable conditions at Hilcrest Hospital.
Police say that TJ Lane is now in custody.
Authorities used a K-9 unit to track down the suspect, who was found about a half mile from the school, not far from his car.
Authorities initially believed the shooting was carried out by more than one gunman, though it was later discovered the student acted alone.
FBI officials confirm the believe that TJ Lane was allegedly the only person involved in the attack. They are currently doing a sweep of TJ Lane's home and the surrounding area for any evidence that could be helpful in the investigation.
However, they will not speculate on the motive for the shootings.
Student Evan Erasmus told officials that the alleged shooter posted a message to Twitter that he was going to bring a gun with him to Chardon, but that no one took him seriously.
Others said that TJ Lane texted people in the days and weeks before the attack.
The FBI and local authorities are now searching the suspect's house, which is being treated as a crime scene. They will be looking for any notes or additional evidence.
More than 1,100 students attend the high school, which is 30 miles east of Cleveland.
Superintendent Joseph Bergant II told WKYC that the culprit is in custody in a juvenile detention centre, but added that he didn't know the extent of the students' injuries.
District Community Coordinator Ellen Ondrey said the Chardon Police Department has the school on lockdown as they secure the area.
A local church is planning to hold a prayer vigil tonight in light of the shootings. Another will be held tomorrow night.
The service this evening will be held at First Baptist Church of Painsville, and is to be led by Rev Peter McCurdy, who was himself a victim of a shooting as a child, WKYC reported.
Grief counselors have also been made available to students as they come to terms with all that has happened today.
Chardon is a city of about 5,100 residents.
"In a time long since, a time of repent, The Renaissance. In a quaint lonely town, sits a man with a frown. No job. No family. No crown. His luck had run out. Lost and alone.
They too should feel his secret fear. The dismal drear. His pain had made him sincere.
He was better than the rest, all those ones he detests, within their castles, so vain. Selfish and conceited.