The criminal proceedings into what Toronto police described as the "largest international drug takedown" in their history have been halted.

The Public Prosecution Service of Canada confirmed to CTV News Toronto on Tuesday that charges in relation to the joint investigation dubbed "Project Brisa" were stayed on Monday.

"No reasons for the stay were provided to the Court in this case," the agency said in a statement.

The results of the investigation, which began in Nov. 2020, were announced with great fanfare at a news conference in June 2021.

"Let me be clear, the size and scope of this investigation in terms of drugs seized and potential harm caused have never been seen before in the history of our service," then Toronto police chief James Ramer said.

"To my knowledge, this is the first time we've conducted a media briefing such as this outdoors to enable to be able to display the magnitude of what was seized."

Behind Ramer were tables displaying more than 1,000 kilograms of illicit drugs. They include 444 kilograms of cocaine, 157 kilograms of crystal meth, 427 kilograms of marijuana and 300 oxycodone pills.

The drugs were allegedly seized when police executed 35 search warrants in May 2021 in the Greater Toronto Area and other cities in Ontario and across the country.

In addition to the drugs, police found $966,000 in cash and a Glock handgun and seized five tractor-trailers and several other vehicles, including a Mercedes G-Wagon.

"The removal of this quantity of drugs destined for the streets of our respective communities has without question prevented countless overdoses, acts of drug-related violence like shootings and other occurrences that diminish the quality of life for our citizens," Ramer said at the time.

Investigators alleged that a group of smugglers used trap door compartments in tractor-trailers to move up to 100 kilograms at a time from Mexico and California to several cities in Ontario.

Several tractor-trailers and other vehicles were allegedly modified with hydraulic-powered trap door compartments to move drugs.

During the news conference, police revealed 20 people, including one youth, were arrested in connection with "Project Brisa" and were facing a combined total of 182 criminal charges.

Defence lawyer Greg Lafontaine, who represents one of the accused, told CTV News Toronto on Tuesday that several factors might have led the prosecution to stay the charges.

"These large project cases are not without their difficulties in terms of being manageable to prosecute. And this is an example of it. Some of my colleagues were attacking the search warrants in a way that led to procedural problems for the Crown, and the police And that, in turn, spun out the time it was taking to get through the trial, which created concerns about the right to have the matter tried within a reasonable time," Lafontaine said.

"And sizing it all up, the Crown determined that it was a case that ought not to be pursued any further."

Lafontaine said his client is happy to have the case behind him, and he'll be able to move on with his life.

"He's always maintained his innocence," Lafontaine said.

When asked for comment, Toronto police declined to make a statement.

- With files from CTV Toronto’s Austin Delaney and Chris Herhalt