Thieves have sawed off more than 500 downtown parking meters from their posts this year and walked away with them, city officials said.

The city of Atlanta has had to replace about 39 percent of its parking meter inventory this year because of the thefts. Although the meters don't contain much money, it costs about $500 to replace each one, said Sandra Jennings, deputy commissioner for the city's transportation office.

"Someone was actually cutting the pole and taking them so they could somehow open the meter head to get the money out," Jennings said.

The city is replacing them with more secure meters. Jennings said the parking meter program pays for itself.

Despite the thefts, little is being done to catch the parking thieves. That's because city officials do not file police reports on the stolen meters, Jennings said. The city's police department said thefts that are not reported are not investigated.