Three students were charged after a teacher was knocked unconscious Monday at an Atlanta high school.

The incident happened at the New Schools at Carver, Channel 2 Action News reported.

During class, several students started turning the lights on and off and throwing things, Atlanta police spokesman Officer John Chafee said. The teacher was hit in the head and knocked out. He was transported to Grady Memorial Hospital for treatment. No information was available on his condition.

Three students were charged with reckless conduct, Chafee said.

The Atlanta Public School system said the incident is a police matter and remains under investigation.