Two recent cases involving police impersonators highlight a growing crime trend in central Indiana, law enforcement officials said.The Indiana Intelligence Fusion Center tracked 36 cases across the state of people impersonating police officers over the past 18 months, 6News' Jack Rinehart reported."There is a terrorism concern," said agency spokesman Douglas Johnson. "I think that when these incidents happen it decreases the confidence the public has in their paid public servants and that's not tolerable for those of us who are working very hard and doing our jobs in accordance with the law."In one of the cases being investigated by Indianapolis police, the impersonator pulled over his victim and eventually got away with $800 cash from the man's wallet."He got out of the car, identified himself as a police officer, produced a badge," said Detective Bob Pearsey. "He said the right things that would lead the driver to believe that he was a police officer."To make a legal traffic stop in Indiana, the officer's police cruiser must be marked or the officer himself must be in a plainly visible uniform, officials said."If it's not clearly marked as a police car and you see the individual and he's not in a uniform, call 911 or drive to the nearest police station or somewhere in public where you can get some help," said Sgt. Matthew Mount.Officials at the Fusion Center said that police impersonators usually have a past for current employment in security work or they've gained knowledge of police work through criminal activity.