WASHINGTON — A few passengers got on a bus in Maryland, thinking it was a good deal. Instead, they were left with a handful of counterfeit tickets.

Now TransIT Services, the agency that operates the bus, has alerted customers to the scam in Frederick.

“Someone was standing near a bus stop selling a multi-trip ticket, that would normally be either $10 or $13  for only $5, and the tickets were counterfeit,” said TransIT Services Director Nancy Norris.

It seemed like a good trade at the time, Norris said, but it left a few customers out of money and out of a ride.

The agency sent out a tweet alerting other customers to the scam. It’s converting all tickets that weren’t already on official card stock to prevent future problems.

“It’s frustrating, mainly because they’re on the way to work, and they go to board the bus and they don’t have valid tickets,” Norris said. “It’s just a hassle for them.”

The system shuttles throughout the city and to Marc trains. It has a new app that riders can use to ensure their tickets are valid.

Norris suggests passengers try downloading their tickets.