Authorities say a teenager pulled out of his Connecticut high school's swimming pool during gym class has died.

East Hartford Fire Chief John Oates says the boy died Wednesday after he was found unresponsive in East Hartford High's pool.

The district's superintendent told parents in a letter Wednesday that "an incident" happened during a gym class in the pool area and that it remained under investigation. He didn't disclose details or the student's identity.

Emergency crews received a report at around 12:30 p.m. of an unresponsive student in the pool. The superintendent says that a bystander was performing CPR when rescuers arrived and that the teen was taken to a hospital.

An autopsy was planned to determine if the boy drowned or if other medical factors were involved.