LIMA, Ohio (AP) — The convicted killer of three Ohio students at a high school cafeteria escaped from a Lima prison Thursday, and a search was underway, police said.

Nineteen-year-old T.J. Lane escaped along with two other inmates and one of the inmates was captured, Lima police Sgt. Andy Green said. A search was underway in woods and a residential area near the prison, he said, and the two escapees are considered dangerous.

Authorities said they do not believe the two men are armed, however. They had no further information on how the inmates escaped from prison. Green said the police were notified about 8 p.m. Thursday evening.

Lane pleaded guilty last year to shooting three students in February 2012 at Chardon High School, east of Cleveland. He said he didn’t know why he did. He was given three life sentences.

Authorities identified the other inmate as Clifford E. Opperud, 45, and said he was serving a sentence for aggravated robbery, burglary, and kidnapping.

Prosecutors say Lane took a .22-caliber pistol and a knife to the school and fired 10 shots at a group of students in the cafeteria. Daniel Parmertor and Demetrius Hewlin, both 16, and Russell King Jr., 17, were killed.

Lane was at Chardon waiting for a bus to the alternative school he attended, for students who haven’t done well in traditional settings.

Before Lane’s case went to adult court in 2012, a juvenile court judge ruled that Lane was mentally competent to stand trial despite evidence he suffers from hallucinations, psychosis and fantasies. At his sentencing, Lane was defiant, smiling and smirking throughout, including while four relatives of the victims spoke.