Nine illegal radio stations have been discovered since March but Shanghai Radio Administration Bureau warned yesterday it is getting ever harder to find the culprits setting them up.
Radio broadcasting equipment was usually located on rooftops in residential complexes. The bureau said most suspects rented apartments to install the equipment.
Sun Jia, who is in charge of the law enforcing department of the bureau, said the equipment was often too small to be visible from the ground. "Most property management companies of the residential complexes said they were not aware of the existence of such equipment," she said.
Sun added that all the illegal radio stations transmitted programs selling medicine and they usually started operating at midnight.
"In some cases illegal radio operators even managed to frequently change the radio frequency to fool law enforcers," she said.
The suspects are still being hunted. Illegal radio equipment was found in Xuhui, Minhang, Yangpu and Putuo districts.