Police are investigating a gold heist at Toronto Pearson International Airport, a location often used to ship gold mined in the province of Ontario.

Canadian officials say more than C$20m ($15m; £12m) of gold and valuables were stolen on Monday 17 April.

The "high-value" aircraft container arrived at the airport in the evening and was transported to a cargo holding facility.

Police believe that is where the heist took place.

The theft could mark one of the bigger heists in Canadian history, including the 2011 and 2012 Great Canadian Maple Syrup Heist, when 3,000 tonnes of syrup valued at $18.7m were stolen from a storage facility in Quebec.

Peel Regional Police inspector Stephen Duivesteyn said their team is investigating "all avenues" and described Monday's incident as "isolated" and "rare".

He said the aircraft container was about 5 sq ft in size, but declined to say how much it weighed.

Officials have also refused to say what airline shipped the cargo, or where the load had come from and its intended destination.

The Toronto Sun reported earlier on Thursday that police thought organised crime groups were involved. Mr Duivesteyn said it was too early to tell.

The BBC contacted the Royal Canadian Mounted Police and Pearson Airport for comment.