Toronto/IBNS: Investigation by Peel Region Police is underway after the theft of a high-value container carrying gold and other valuable items worth an estimated $20 million were stolen from Toronto Pearson International Airport, police reported.

The container arrived on a plane early Monday evening, Insp. Stephen Duivesteyn, spokesperson for Peel Regional Police, told reporters on Thursday.

"An aircraft arrived here at the airport in the early evening. As per normal procedure, the aircraft was unloaded and cargo was transported from the aircraft to a holding cargo facility,"  Duivesteyn reportedly said while announcing the theft.

He added that  after the cargo was secured in the holding facility, the container holding gold and other "high-value goods" worth $20 million was removed illegally.

Duivesteyn did not name the airline and declined to say where the plane arrived from, adding it could jeopardize the investigation.

Duivesteyn reportedly said the plane was unloaded according to normal procedure and its cargo taken to an airport holding facility before it was "removed by illegal means."

The theft was reported shortly after it was discovered, he said and added that no one has been arrested.

Police do not yet know where the gold was headed to or if it is still in the country, he said.

No suspect information has been released.

"This is very rare," Duivesteyn was reported saying, adding that it's too early to know if the theft was carried out professionally.

(Reporting by Asha Bajaj)