Facebook is monitoring its users' chats and posts on the social networking site for any suspected criminal activity, and alerting police about suspicious behaviour, according to a report.
Using 'smart' software, Facebook looks for certain phrases, exchanges of personal information and vulgar language.
If it comes across a suspicious exchange it flags it with Facebook's security personnel who then assess it and decide whether to contact police, News.com.au reports.
According to the report, Facebook said it works with police 'where appropriate and to the extent required by law to ensure the safety of the people who use Facebook'.
"We may disclose information pursuant to subpoenas, court orders, or other requests (including criminal and civil matters) if we have a good faith belief that the response is required by law," the firm said.
Facebook said this includes requests from outside of the US as well as sharing information with 'other companies, lawyers, courts or other government entities'.