Winnipeg Fire Paramedic Service (WFPS) crews responded to an ammonia alarm at a Winnipeg community centre just after midnight Friday.
The WFPS said it was called to the River Heights site of Corydon Community Centre on Grosvenor Avenue, which houses an indoor hockey rink.
A buildup of ammonia, which is commonly used in rink refrigeration systems, was found in parts of the building by the WFPS hazardous materials unit.
Crews were able to ventilate the building, which was empty at the time, after finding and mitigating the leak. No injuries were reported.