CHICAGO (CBS) — A Mount Greenwood gas station has been shut down by the city, after officials found water mixed into the fuel supply.

Ald. Matt O’Shea (19th) said his office received a call from a constituent whose car stopped running shortly after buying gas at the Citgo at the corner of 111th Street and Lawndale Avenue.

The man had to have his car towed, and his mechanic discovered bad gas in the car. O’Shea said it will cost the man hundreds of dollars to fix.

“We immediately called the Department of Business Affairs and Consumer Protection for the city. They were out there within the hour. They conducted three separate tests, all confirming that in fact there was water in the tanks. There was in fact four inches of water,” he said.

The alderman said the station’s pumps were ordered shut down until the problem is corrected.

O’Shea said the owner faces fines of $50 to $2,000 per pump.

It has not yet been determined how the water got into the tanks.