Halifax Regional Police are warning motorists that the car beside you on the road might not be roadworthy.

During a large traffic blitz on Tuesday, police say they found more than two dozen vehicles with phoney MVI stickers.

People in the auto-repair industry believe this is just the tip of the iceberg.

After a dozen years in the industry, Mark Thepen has pretty much seen it all.

Working at a shop in the north end of Halifax, his day can be filled with any number of jobs, big and small.

The shop also offers motor vehicle inspections, something required by law in Nova Scotia, and fairly regularly, Thepen will spot a fake.

"You'd be surprised," Thepen said. "People will do pretty much anything they can to fake a sticker."

Decades ago, annual motor vehicle inspections were required across Canada, but now the Maritime provinces are the only ones that still require inspections every year or two.

Hundreds of thousands of motorists follow the rules, but a significant number don't, picking up convincing black-market stickers.

Police found 27 of them in simultaneous checkpoints in Halifax and Dartmouth on Tuesday.

"Even one false MVI is a road safety issue because, keep in mind that, from what we have found anyway, these sell anywhere from $180 to $250," said Sgt. Monier Chediac of Halifax Regional Police Traffic Services. "And so, a lot of times, if someone is buying a sticker at that cost, it's to bury or conceal more significant issues -- sometimes in the thousands of dollars."

Half of the 27 vehicles had bald tires or faulty brakes. One had a rusted-out frame.

The Nova Scotia government says it too is concerned, but the onus is on drivers to obey the law.

"Vehicle owners must ensure their vehicles are properly inspected by a licensed mechanic, at a reputable garage, and all necessary repairs done", wrote Peter McLaughlin, a spokesperson for the Nova Scotia Department of Transportation and Infrastructure Renewal. "It is also suggested that if you are buying a used vehicle, you should have it inspected (MVI), by a licensed mechanic, before you purchase the vehicle."

Thepen says he and other shops record MVI information on every vehicle they work on, but there are still plenty of fakes on the road.

"Usually, if they have a fake sticker, they are usually fully aware that they have a fake sticker," said Thepen.

Police say they'll continue to target shady stickers because no one should have a licence to lie.

In all, 94 tickets were issued during Tuesday's blitz. Halifax police say 29 vehicles were towed and 20 others had real MVI stickers, but they were expired.

With files from CTV Atlantic's Bruce Frisko.