First responders at a high school explosion now say an 18-year-old boy originally reported as dead is not -- he was resuscitated with a pulse.

Eric Leighton is in critical condition at an Ottawa hospital.

Friends say he played hockey and is supposed to graduate this June.

Paramedics say they are treating several who were injured in the blast.

Emergency crews were called to Mother Teresa Catholic High School Thursday morning after a 55-gallon drum of peppermint oil exploded in an auto-shop class.

Students tell CTV reporters at the scene they were able to feel the blast in their classrooms and that the entire school shook.

A team of hazardous material experts are on the scene investigating alongside police.

A representative from the Ottawa Catholic School Board says students have been evacuated to Longfield Davidson Heights High School on Berrigan Drive.

Parents with students at Mother Teresa are asked to call the school board at 613-224-2222.