Toronto police there’s nothing to suggest a criminal element is involved in a mysterious underground chamber found near a Pan Am Games venue in the north end of the city.

Deputy Chief Mark Saunders says police are asking the public’s help in figuring out who built the chamber and why.

Saunders says the chamber was discovered in a densely wooded area by a conservation officer in January and is located 25 metres from the fence of the Rexall Centre.

An investigation has determined that the chamber was used at some point during the winter.

Saunders says those responsible for building the underground structure clearly had some level of expertise in ensuring its structural integrity.

He says police found plywood wall supports, a generator, moisture resistant light bulbs and a sump pump in the chamber.

He says they also found a rosary with a Remembrance Day poppy in the chamber.