CLEVELAND, Ohio -- The "hacktivist" group Anonymous began digging into the background of Timothy Loehmann, the rookie police officer who fired the shots that killed 12-year-old Tamir Rice.

Anonymous used BeenVerified, an online resource that conducts basic background checks using public records, to uncover some basic information on the 26-year-old cop, including his phone number and address.

Police today identified Loehman, along with Frank Garmback, the sixth-year officer who was with him at Cudell Recreation Center when Tamir was shot.

The background check found Loehmann's only run-in with the law was an underage drinking offense from 2007 when he was 19. He pleaded guilty in a Seneca County court, the document shows.

The record also lists names of four possible relatives and two addresses for potential family members.

The Tamir Rice shooting caught the attention of the "hacktivist" group Monday, when it took credit for shutting down the city of Cleveland's website. The site is now up and running.

Anonymous, which describes itself on Twitter "as a signal boost for Anonymous operations, resistance movements, & real journalism" has been a vocal advocate for the protests in Ferguson, Missouri since an officer there shot 18-year-old Michael Brown.

Anonymous reports its activities on Twitter, using the handle @YourAnonNews.