New York City officials have fined the owner of a Brooklyn manufacturing building after inspectors found illegally constructed rooms on the roof being rented to tourists who booked the accommodations through Airbnb.

The Mayor’s Office of Special Enforcement, responding to reports of illegal hotel activity, found five residential units constructed on the roof of the two-story building next to the Manhattan Bridge in the borough’s Dumbo neighborhood. City inspectors say the certificate of occupancy calls for manufacturing in the building itself.

The Daily News reports three of the rooms were occupied by tourists from the U.S. and overseas. The owner of the property was issued a vacate order and fines that could add up to $55,000.

Attempts to reach the Airbnb host and building owner were unsuccessful.

(AP)