Stop signs are there for a reason. When automobiles first became available for the masses, there were so many accidents that something universal had to be done. Laws were created and road signs developed, forming eventually to what we know today as the Rules of the Road. Alongside, a licensing system and driving school programs were instituted to ensure that the biggest source of accidents, the human, are well educated and capable to abide by the rules and navigate the roads well.
So when a component in the road system fails, generally the driver, then accidents are bound to happen like in this instance in Serpukhov, Russia. The driver in the gray sedan ran a stop sign and collided with a blue work van.
After an accident a person generally goes through a series of emotions such as being dazed, confused, shocked, and eventually being angry. The men in the blue work van were seemingly angry to begin with even before the collision (perhaps because they were driving a blue work van?) that they quickly jumped out and assaulted the driver of the gray sedan. A fairly short but tense street fight ensued between the passengers. Shortly, a fellow motorist in a BMW (BMW, really?) pulled over and attempted to mediate the situation.
Moral of the story, obey the street signs! And if you see angry people coming towards you, just lock the door and roll up the windows (if you still have them)