Don't stop and offer assistance at accidents. They may be staged by criminals. Instead, drive to the nearest phone. Call the police and give the location of the accident. Always look in the back seat before you enter the car.
Police use flashing red and blue lights.
If another vehicle bumps your car from behind do not stop. Go to a well-lit service station or the nearest police station. If someone attempts to take your car by force, let them. Possessions can be replaced, you can't. Report the incident to the police immediately.