Sixty people were arrested Tuesday morning in a series of pre-dawn raids across Canada as part of a joint investigation involving Toronto police.

Toronto police said more than 900 police officers, including 400 heavily-armed tactical officers, were involved in simultaneous raids in Toronto, London, Hamilton, Durham, York and Peel regions, Windsor, Ottawa, Calgary and Surrey, B.C.

In all, police executed 67 search warrants as part of a sting dubbed Project Marvel, which targeted organized crime.

Charges against the 60 arrested suspects - including 10 young offenders - include attempted murder, firearms trafficking/importation, drug trafficking and robbery, as well as shooting and prostitution offences.

Some of the suspects are accused of smuggling firearms across the Canada-U.S. border.

The investigation was launched last May by the Toronto police integrated gun and gang task force, in partnership with London Police Service, Waterloo Regional Police Service and Ontario Provincial Police, after a street robbery and shooting in a northwest Toronto neighbourhood.

"The project quickly developed into a criminal [investigation] involving two criminal gangs, the Young Buck Killas and the G Siders," Supt. Chris White of Toronto police's organized crime unit said at a press conference Tuesday afternoon.

As police dug deeper, the investigation spread to Windsor, Hamilton, Peel region, York region, Durham region, Ottawa, Renfrew, Sask., Calgary, Edmonton, Ford McMurray, Alta., and Vancouver.

"It revealed a level of mobility among street gangs that we had not previously seen," Toronto police Chief Bill Blair said of the investigation.

About 20 police agencies were involved in the operation, in addition to members of Canada Border Services Agency and the U.S. Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF).

Police seized an undisclosed quantity of firearms, ammunition, drugs and cash in Tuesday's raids.

Specifics on the items seized, as well as the charges against those arrested, will be addressed Wednesday, police said.

"I'm very hopeful that those neighbourhoods will be safer places," Chief Blair said of the project's impact.

Police said the investigation is ongoing.