Investigators say a video of people using a blowtorch to get into an ATM was posted by police on YouTube last October and received more than 100,000 views.
Halton regional police say the ATM thefts began on Oct. 24, 2010, and they say by Thursday the thieves had hit more than 70 in Ontario and more than 60 in Quebec.
Three suspects were arrested in Niagara and Toronto, and a fourth was arrested in Laval, Que., on Thursday.
Police seized clothing, tools and communication devices, and say more than $10,000 from an ATM break-in on Thursday has been recovered.
Sixty-five charges have already been laid against the accused and Halton police say more than 50 additional charges are anticipated to be laid by other jurisdictions.
"We are extremely grateful to our colleagues across Ontario and Quebec and to the public for their assistance in this investigation," Det. Sgt. Anthony Odoardi said Friday.
"Effective teamwork and co-operation between investigators in Halton, Toronto, Niagara, Hamilton, Waterloo, York, Peel, Durham, Ottawa, Montreal and Laval was essential to making arrests in this 16-month investigation," he said.