An entire city's train traffic was brought to a stop Saturday by a rat that authorities discovered was stuck in a hotel signal box.

Stockholm residents suffered a three-hour traffic delay, with officials primarily failing to find the source of the problem. Questions about the transit problem were answered when the police finally found the large rat inside the signal box at the basement of a local Sheraton Hotel.

"We received reports that a large rat had come into contact with an electric rail," Sweden's The Local quoted Karin Ullman as saying, Ullman is spokesperson for the electric company Fortum.

"It switched everything off," Ullman added. "The reason it took three hours was that the fault needed to be exactly localized."

The power interruption was also experienced from 5 a.m. to 8 a.m. by the hotel, and nearby buildings, reported the UPI.