(Radio Iowa) – After several fender-benders involving Iowa school buses this week, including some with injuries, authorities are reminding drivers about the importance of using caution whenever they spot the slow-moving, yellow vehicles. Trooper Paul Gardner, a public resource officer with the Iowa State Patrol based in Fort Dodge, says many schools started classes this week and thousands of buses are navigating the state’s roads, carrying their cargo of kids.

“When they’re on the road and they see a school bus, please keep that in the back of their mind,” Gardner says. “That school bus may be coming up to a stop. When you see the yellow-amber lights flashing, that means the bus is preparing to stop, and once the red stop lights come on and the stop arm’s extended, it’s illegal to pass at that point.”

Motorists may get impatient and try to zip around the bus before it comes to a halt, but the patrolman says that could be both a life-threatening — and an expensive — mistake. “It’s illegal to pass a school bus when it’s stopped, red lights and stop arm are activated,” Gardner says. “So when a driver is caught in violation of that, they could face a minimum fine of $345 and a suspended driver’s license. It’s definitely a dangerous violation.”

State lawmakers adopted Kadyn’s Law in 2012 after the death of seven-year-old Kadyn Halverson of Kensett, who was fatally hit by a pickup in 2011 while trying to cross the road to board a school bus. The law raised criminal penalties for passing a stopped school bus.