FREDERICK, Md. (AP) — Frederick County authorities are showing off some technology designed to catch drivers who illegally pass school buses.

Officials from the sheriff's office and the public school system planned to demonstrate the school-bus cameras Tuesday morning in Frederick.

The Frederick News-Post reports that Frederick is the first county in Maryland to permanently install cameras on buses under a state law passed last year. The state education department says Charles, Montgomery and Washington counties are running pilot programs this year.

The Frederick system is supplied by Xerox Corp. It records video of drivers who illegally pass a bus with its "stop" arm activated. Violators face a $125 fine.

Officials say 40 of the county's 435 school buses will be outfitted with the camera by the end of the school year.