VERY VERY SUS this is a common thing now, fake policeman will attempt to pull a nice car over while he has your attention another person gets in your car and drives off!!! as im a prison officer i can get into the police computer system to check the lastest type of crimes..
TIP GUYS SERIOUSLY dont ever stop unless you see geniune police lights, and never get out of your car until the officer instructs you to. if you are unsure it is a real officer you are fully within your rights to ask for proof of id, you can take there reg number, badge number even take a photo of there car, be cautious and polite BUT DONT BE BULLIED....
If it is an unmarked car 9/10 it will have full camera and speed detection kit in, But again if you are un sure ask, ( you are NOT commiting a crime by protecting yourself )
KEEP YOUR CARS KEYS SAFE AT ALL TIME TOO....
sounds harsh i know but this is the S**T world we now life in ! !
ANY questions pls ask me :d