Video of crash 'shows how quickly things can go wrong' when you don't move over

The video starts with a vehicle parked on the right side of I-235 in Iowa.

Cars pass. Then you see a white car in the lane closest to the pulled-over vehicle.

At about 8 seconds into the traffic camera video posted by the Iowa Department of Transportation, you see that white car drift to the right, closer and closer to the vehicle parked on the side of the interstate.

Then, at the 12-second mark, the two vehicles collide. The white car flips into the air and lands on its top in the interstate. The other vehicle is pushed further into the grass.

Some drivers quickly pull over to help, while others pull off to the other side. And traffic begins to slow down.

The Iowa Department of Transportation posted the minute-long video to Twitter in anticipation of the state's expansion of the "Move Over, slow down" law that goes into effect on July 1.

"This video from one of our I-235 cameras shows how quickly things can go wrong when you aren't paying attention/moving over," the post says. "Amazingly, no one was seriously injured."

The expanded law requires that all drivers in Iowa "change lanes or slow down when approaching ANY vehicle with flashing emergency light or hazard lights activated," according to Move Over Iowa. That includes tow trucks and other utility vehicles. Previously, the 2002 law only required drivers move over or slow down for emergency vehicles stopped on the highway, KWWL reported.

All 50 states have a "Move over" law, according to the National Highway Traffic Safety Administration, but 71 percent of people were unaware of these laws as of 2013, according to the department. The law varies by state, but a state-by-state list is available with AAA.

Last year, 53 law enforcement officers were killed in traffic-related incidents and 15 were struck and killed while outside of their vehicle, according to NHTSA.