Posted by an anonymous users, the data has been sitting there since February 9, and is accompanied by a message protesting the brutality of the SPVM, Global News reported.
"This is a warning to withhold violence during the Education Summit, and any following show of resistance. This is a warning to disobey your orders, to find the dignity to know the difference between right and wrong, and the courage to act on that. We are only asking that you open your eyes to the injustice you commit, the corruption you enable and the name you are defending. This is your last warning," the group wrote.
"As you have taken our identities, we now take yours. You have forgotten your actions not only reflect onto you as a Police Officer, but also reflect on you as a person; in uniform, and outside of your uniform, you will be judged."
The SPVM has still not confirmed whether the leaked data does, indeed, come from their servers, and whether it is accurate.
According to CJAD 800's Laura Casella, the same data along with additional documents and pictures stolen from the servers have been uploaded to Dropbox and links for the download disseminated via Facebook and Twitter.
This drop allegedly contains pictures of and information about undercover police agents, unmarked police vehicles, and a secret police station.
Twitter user Michael Forian (@Forian), former reporter and producer at CJAD 800, has published links to several photos of what appear to be undercover agents and vehicles (along with their registration plates), but has declined to give out the link to the actual documents.
According to Montreal police spokesperson Ian Lafreniere, the leaked photos have been circulating on the Internet since last year, but that they "don't recognize these people as Montreal police officers."
By subscribing to our early morning news update, you will receive a daily digest of the latest security news published on Help Net Security.
With over 500 issues so far, reading our newsletter every Monday morning will keep you up-to-date with security risks out there.