According to the China Youth Daily report, police officers in Gucheng county, Hubei Province have confiscated over 6,000 components of wireless examination cheating devices including ejectors, acceptors and earphones.
Police told the reporter that the devices manufactured by the gang accounted for 60 percent of China's market and have been sold to countries such as Thailand and Myanmar.
Investigations found that the cheating devices, which had been used in graduate entrance exams, judicial exams and other vocational certificate tests across the country, were manufactured in an electronics factory in Shenzhen, South China's Guangdong Province.
The factory distributed the devices to agents in other provinces, which then sold them to training centers or students.
The factory's owner surnamed Li, 47, who used to be a journalist in Tianjin, confessed that he decided to quit his job and start the business after recognizing that the technology of the device was simple but profitable.
"An ejector, which costs 1,500 yuan ($225), was sold for 2,200 yuan while an acceptor, which costs 70 yuan, was sold for 150 yuan," police officer Jiang Daomin told the reporter. "They can transmit and accept messages wirelessly within 2 to 3 kilometers."
According to the police, Li's factory owned five production lines and could earn 30 million yuan annually. He had been investing more in new technology for his device and the concealed earphone the factory produced was very hard to spot.
Li had been sentenced to one year and seven months in jail in 2014 for the crime of illegal sale of special equipment for espionage.
Currently, a total of 276 suspects, five manufactures, 58 agents and eight training centers are under investigation in the case, said the police.
China's criminal law stipulates that organizing or helping organize exam cheating, providing test questions and answers, as well as surrogating exams for others, are deemed as a crime.