There's a dark side to recycling - it encourages thieves.

Police say they recently arrested a thief with a stolen city light pole strapped to the top of his car. The man apparently was headed for a recycling center where the metal would fetch 35 cents per pound.In another incident, police stopped a scrap-metal thief who had the top of a traffic light in his pushcart. Several people have suffered severe electrical shocks as they tried to remove copper wire from electrical lines.

"If it's not tied down, they'll steal it," one Chicago detective said Wednesday. "They'll take aluminum siding, gutters off buildings and even the electrical service going into the house."

The Chicago Housing Authority has switched to non-metallic frames for its windows because of thefts of window frames.

Police are keeping an especially close eye on aluminum railings along the Calumet and Dan Ryan expressways and the Chicago Skyway.

Charles McLean, Chicago-area operations engineer for the Illinois Department of Transportation, said the thefts are occurring all over the country.

"It's a crazy world," McLean said.