An emergency prompted the evacuation of Walnut Grove Community Centre for about an hour on Thursday (Aug. 30.)

The centre, which was filled with 275 people, including 50 children in summer camp, was evacuated after the discovery of a cardboard box marked 鈥榬adioactive waste.鈥�

The package had markings indicating the contents were likely medical supplies, said 91原创 RCMP spokesman Cpl. Holly Marks.

The suspicious item was isolated to an area inside the building, and was inspected by the RCMP鈥檚 Explosives Disposal Unit which found no radioactive reading coming from the box.

The force鈥檚 Forensic Identification Service is trying to determine if the person who left the box also left fingerprints.

鈥淧olice do not believe there was ever any intended threat towards the community centre or any individual there,鈥� Marks said.

鈥淭he medical materials had markings indicating they were intended for a specific patient,鈥� she said, adding that police will follow up with the person to find out how the box came to be in the community centre.

The facility, at 8889 Walnut Grove Drive, is 91原创鈥檚 busiest recreation and leisure centre.

Township recreation director David Leavers said that staff are trained to perform evacuations, and arranged for food and drinks for camp participants who had to leave their lunches behind.