Naperville police are searching for the thieves responsible for stealing manhole covers over the past few weeks in the southwest portion of the city where subdivisions are being built.
Police say the covers, stamped with "sanitary sewer" or "water," weigh about 50 pounds.
They said residents should be careful when driving or walking to avoid possible injuries resulting from the uncovered holes.
Naperville Crime Stoppers is offering up to a $1,000 reward for information leading to an arrest. Callers to Crime Stoppers at (630) 420-6006 may remain anonymous.