A small diesel spill occurred around Cott Beverages Inc. on Cliffstar Avenue in the city of Dunkirk after a tractor-trailer reportedly rolled down the hill and punctured a hole in the gas tank on the side of a second tractor-trailer. The incident occurred shortly after 3 p.m. Wednesday, according to the Dunkirk Police Department. Both semis were unoccupied at the time, and the runaway truck apparently did not have its parking brake on while stationary. Police said the gas tank had a capacity of 125 gallons, but much of the fuel was saved. Some did manage to drain into the storm sewer, but there is no concern at this time. No one was injured as a result of the incident.