Philadelphia police are trying to figure out who is running an Instagram account that identifies witnesses of violent crimes.
Authorities are investigating an anonymous social media account that they say has been identifying witnesses in violent Philadelphia crimes with the stated intention of trying to "expose rats."
The Philadelphia Inquirer says the "rats215" account on the photo sharing site Instagram has posted photos, police statements and testimony identifying more than 30 witnesses since February.
Lt. John Walker of the Southwest Detectives division says police learned of the account last week when an officer monitoring Twitter spotted photos of a witness and court records from an attempted shooting.
Walker says investigators are now working to identify the account-holder. He says such accounts "shoot an arrow through the heart of the criminal justice system."