London police confirmed they’re investigating after sandwich board signs that were taken recently by the City of London were mysteriously returned to businesses.

Two weeks ago the city took about 60 of the signs from outside of businesses, saying they were in violation of a bylaw. Store owners need a licence to put their signs on public sidewalks. The licence is free if a business owner can show proof of insurance.

The city says it went store to store last spring warning that a crackdown was coming.

While store owners were upset, city officials said the signs would be returned for $175.

Then the signs appeared in front of businesses last weekend.

The police are not sure who took them and returned them at this point, but there is a video from Grooves Records showing a man dropping off a sign outside of that store on Saturday.