Canadian police said Thursday they are investigating a heist of more than Can$20 million (US$15 million) in gold and other "high-value" goods being moved through the Toronto airport.

The gold and valuables arrived Monday evening in a container that was offloaded from a plane and securely stored in a cargo holding facility, Peel Regional Police Inspector Stephen Duivesteyn told a news conference.

It was reported missing shortly after.

Duivesteyn said the "high-value container was removed by illegal means from the holding facility." He would not comment on how the theft unfolded or who might be behind the caper.

"Our investigators have got their eyes opened to all avenues," he said. "We're looking at all angles on how this item was stolen."

The Toronto Sun reported that the thieves made off with 3,600 pounds of gold, citing anonymous sources saying authorities are looking at organized crime groups in the region.

"This is very rare," Duivesteyn said, describing the airport theft an isolated incident that has had no impact on the travelling public.

He said it was too early in the investigation to say if it was a professional theft or a crime of opportunity.