By CBSBoston.com Staff

SALEM, NH (CBS) – High levels of carbon monoxide forced the evacuation of a hockey rink in Salem, New Hampshire Friday.

Firefighters were called to the ICenter for an unrelated medical issue when suddenly the carbon monoxide detectors they wear on their gear went off.

READ MORE: Man In 'Grave Condition' After South Shore Plaza Shooting In Braintree; No Arrests Made Yet

There was a hockey game underway at the time. Crews moved the game to a rink in a part of the building that was safe.

READ MORE: Driver Killed By Commuter Rail Train In Wilmington Identified; MBTA Says 'Human Error' Focus Of Investigation

“It was at a level that it would be or could be a problem if people were in the building for a few hours like for a game,” Salem Fire Chief Larry Best said.

MORE NEWS: Vigil And March Held In Belmont For Henry Tapia, One Year After Being Killed In Road Rage Confrontation

Firefighters are not sure if the Zamboni or the HVAC system caused the high levels of carbon monoxide.

CBSBoston.com Staff