Police say at least nine manhole covers have been swiped this month.
Lt. David Young says that's about as many manhole covers that the city loses in an entire year.
Investigators aren't sure why anyone would steal a Lufkin manhole cover, especially since the name of the East Texas city is worked right into the metal.
Police are concerned somebody could get hurt coming upon an unexpected opening in a road.
Authorities believe the thieves might be trying to sell the 150-pound manhole covers for scrap metal.
Lufkin is 115 miles northeast of Houston.