Toronto bunker mystery: Police unsure who built underground chamber

This image released by Toronto police shows the 10-metre bunker.

Toronto police are searching for the builder of a mysterious underground bunker, but say there was nothing to suggest any criminal activity was involved.

The bunker was discovered on Jan. 14, and is just a few hundred metres from the Rexall Centre, also known as the Canadian Tennis Centre, which will be hosting Pan Am tennis competitions this summer.

It was built in a wooded area just south of the tennis courts, Toronto Police Deputy Chief Mark Saunders said at a news conference Tuesday.

Saunders, who is the executive officer for Pan Am Games security, said there is "robust security" in place for the Games. He said security officials have not received any direct threats.

Police are still trying to find the builder or builders, but Saunders said that the bunker wasn't thought to pose a public safety threat.

"I don't have any evidence that suggests criminality at this point, but bear in mind I don't have the intent behind this at this point. That could change. I'm open to anything right now," he told media.

The bunker measured 1.9 metres tall by 0.9 metres wide by 10 metres long, police said. It appeared to have been built by hand, but with a "considerable amount of sophistication," Saunders said.

The walls were supported by plywood planks, and lights were installed inside. A gas-powered generator and tools were found inside, and a poppy affixed to a rosary was nailed to the wall.

Police found a gas can, food and drink containers, work gloves, a sump pump and a wheel barrow during their investigation.

Officers do not believe the builders intended to use the bunker for any type of criminal activity, Saunders said.

Police did not say how long ago the bunker had been built, but said that it had been used at some point during the winter.

Here's what we know so far about the underground chamber:

Anyone who saw something suspicious in the area or saw someone with building materials is asked to contact police. Anyone with more information is asked to call police at 416-808-3100, or Crime Stoppers anonymously at 416-222-8477 (TIPS).

This image released by Toronto police shows the 10-metre long bunker

This image released by Toronto police shows the entrance to the bunker

Image released by the Toronto Police Service shows the bunker

Image released by the Toronto Police Service shows an item from the bunker

Image released by the Toronto Police Service shows items from inside of the bunker

Image released by the Toronto Police Service shows the bunker

Image released by the Toronto Police Service shows outside of the bunker

This rosary with a poppy was nailed to it was found inside of the bunker

Image released by the Toronto Police Service shows items from the bunker

In this aerial view from the CTV News chopper, the wooded area where the bunker was found is visible. The Rexall Centre is at the top of the image.

Location of the Rexall Centre -- also known as the Canadian Tennis Centre (CTC) -- known also as the Rand Pan Am Athletes Centre (YOR) as seen in this Toronto 2015 Pan Am map. This bunker was located in the woods, just a few hundred metres from York University and the Rexall Centre.