The app surfaced data from a state registry and a subdirectory on the state agency's website.
Information about medium and high-risk offenders - including "complete home and work addresses – street number and name, as well as municipality and post code" - has been made available to the public.
"The new Facebook application is designed to make that information more readily accessible," the agency said.
"With Halloween around the corner, parents now have another tool to learn where offenders live so they can ensure their children stay away from those locations, as well as strangers' homes," the division's acting commissioner Sean Byrne said.
"The Facebook app puts that important information at parents' fingertips, whether they are at home or on the go."