Toronto police have arrested five people after they allegedly used fraudulent debit cards to buy monthly transit passes at TTC vending machines.

Police said in a morning news conference that they've discovered $180,000 in losses after they arrested the men on Sept. 27.

Four of the men were arrested outside the North York Centre subway stop, allegedly in possession of 168 counterfeit debit cards and 29 TTC monthly passes. A fifth man was arrested shortly thereafter.

The TTC first became aware of the purchases earlier this year, and worked with Interac to identify video images of several suspects and to develop a pattern of their activity.

The police were called in and Project Rocket was launched Sept. 19, resulting in arrests only a few days later.

Det. Ian Nichol of the Financial Crimes Unit said police also executed a search warrant at a residence in the Marina Del Rey condominium complex on Lake Shore Boulevard where they found a "manufacturing lab."

It allegedly included 105 counterfeit debit cards, numerous stolen point-of-sale terminals, and tools used to steal debit and credit card data.

Nichol said the lab was likely being used to build altered terminals to capture PINs and card data.

The men face a combined 33 charges including conspiracy to commit an indictable offense and fraud over $5,000. More charges are expected once they analyze the terminals, Nichol said.

He said some of the cards were compromised at restaurants outside of Toronto. The TTC vending machines were targeted because they didn't have the new chip technology, which is less vulnerable.

Nichol warned businesses to keep a close eye on their point-of-sale terminals.

"It only takes a few seconds to switch them out," he said.