Thanks to new cameras, drivers who don't obey school bus passing laws could face a hefty fine - on the spot.

Exterior cameras have been put on 120 of Seattle Public Schools' 379 buses. The cameras work similarly to school zone cameras. If a violation is detected, cameras will get video of the car and license plate. The footage will go to the King County Sheriff’s Office, where officials will determine if a violation occurred.

The program began Monday. Drivers captured on video now through Oct. 1, 2017, will receive a warning letter to educate them about the program.

Starting Monday, Oct. 2, the King County Sheriff’s Office will begin issuing $419 citations to drivers that are caught on camera.

A pilot program placed cameras on 10 school buses traveling the busiest routes in Seattle. Over that 112-day period, nearly 600 vehicles passed the buses illegally.