PORTLAND – The Maine Turnpike Authority is about to get tough with toll cheats.

Starting Monday, about 800 letters will be sent to motorists who were recorded passing through tollbooths without paying in the Maine Turnpike’s first effort to collect tolls that go unpaid.

Each letter will be accompanied by a photo of the scofflaw’s license plate as the vehicle passed through a toll plaza.

Turnpike spokesman Dan Paradee said authorities focused on repeat offenders, not those who made a one-time mistake.

“We were not interested in nailing the person who mistakenly drove through an E-ZPass lane a single time. We are interested in letting repeat violators know that the enforcement system is working,” Paradee said.

Last month, an estimated $32,760 went unpaid at Maine Turnpike tollbooths out of total collections of $7.3 million. The registered owners of cars that failed to pay will receive letters asking for the money owed.

If the notice is ignored, the owner faces fines of $50 for the first offense, $100 for the second offense and $150 for each successive offense. Failure to respond could result in a suspended vehicle registration.

The technology has been in place to catch scofflaws since 1997 under the old Transpass system, but officials did not have confidence in the system’s accuracy. That changed in February when the state switched from the Transpass to E-ZPass.

Cameras are set up in each lane of the toll plaza, and they take a picture of the license plate of vehicles that pass through without paying.

The license plate numbers are transmitted to the turnpike headquarters and entered into a database.

The system has an accuracy rate of better than 99.95 percent, said Richard Somerville, the turnpike’s E-ZPass manager.

Paradee said some toll cheats have been caught 60 to 70 times a month. While cheating accounts for only 1 percent of all turnpike transactions, it’s important to law-abiding motorists to know that cheaters aren’t being given a free ride.

“We think this will be very popular with the other drivers,” Paradee said. “We think everyone wants to see the system respected.”