MONTREAL -- The Laval fire department evacuated L'Aquarelle School in Laval after carbon monoxide levels were very high Saturday.

A spokesperson from the Laval fire department said 12 children and one adult were evacuated from the school's gymnasium around 1:45 p.m. and taken to the hospital as a precaution.

Sensors detected carbon monoxide levels as high as 400 ppm, which is considered very high.

Urgences-Sante was contacted and checked the 13 individuals. None of them showed symptoms of carbon monoxide poisoning.

There were some individuals in the school earlier Saturday morning and the Commission scolaire de Laval will follow up and contact all who may have come in contact with the gas.

Maintenance crews are looking into the problem that may have arisen in the school's heating system.

The school will be closed until the source of the leak is found and repaired and levels return to normal.