When I checked, there was a mazda 6 license plate with a red flag?

You can see that this is a deck of cards. FAW Liu Ma and FAW Hongqi are both a group company, but it is impossible for the two cars to use a set of procedures, so the deck is obvious. According to what you said, it should be the red flag license plate of Liu Ma. Liu Ma car owners (or related personnel) should be punished and their vehicles should be detained. If an accident occurs and you escape, you should be investigated for criminal responsibility.