An ammonia leak at Gateway Recreation Centre about 9:30 a.m. this morning sent in two youths and an arena attendant to hospital for treatment.
The youths, who police said are in stable condition, were participants in the Rick Heinz summer hockey camp for goaltenders being held at the rink.
Gateway Road, between McIvor and Bonner avenues, is closed while fire and hazardous materials crews clean up and inspect the area. Motorists and pedestrians are being asked to avoid the area.
About 20 players between the ages of 7 and 17 who were participating in the camp were safely evacuated, some in full equipment.
The children were given their pizza lunch outside on the nearby baseball field and were told they would not be going back on the ice. Today was the last day of the camp.
Gateway Community Centre manager Denis Van Laeken said the leak was not major and expected programming at the facility to resume Sunday.
He said the Sami Jo Small female hockey camp and Pro Ambitions Hockey camp scheduled for the facility next week would not be affected.