Ten mainlanders were arrested for hacking the computer systems and blackmailing 14 member firms of Hong Kong's Chinese Gold and Silver Exchange Society in March, according to Xinhua.
Exchange president Haywood Cheung Tak-hay told the South China Morning Post it was 'good to see Hong Kong and mainland police bring the guilty to book so quickly'.
Cheung said the local gold bourse reported the cybercrime to Hong Kong police in March after some members complained their computer systems had been attacked.
'There was a common pattern. Some firms found that their customers could not access the computer systems because they had been blocked by the hackers. The hackers then demanded a payment of about 100,000 yuan (HK$122,540) to free up the systems to resume normal operations,' Cheung said. 'In some cases, the hackers did not hack the computers but only threatened to do so unless the firms paid up. Some firms that did not want their businesses interrupted paid the money.'
Four Hong Kong gold trading firms paid a combined 310,000 yuan into mainland bank accounts nominated by the hackers. The others refused to pay and reported the matter to the exchange.
'Initially we thought these were unrelated incidents but later we found a pattern as all the victims had the same mainland software supplier. We thus reported the case to the police,' Cheung said.
'The exchange has since strengthened its IT system to prevent hacking attacks. We want to remind traders that if they face any blackmail threats like that, they should inform the exchange and report it to the police and not pay money.'
Xinhua quoted a Hunan police spokesman yesterday as saying the 10 arrests were the result of more than three months of investigation with Hong Kong police. Six of those arrested, believed to be the masterminds, were charged with criminal offences. Police seized 20 computers, three cars, 33 bank cards and 10,000 yuan in cash from the detainees.
Police did not identify those arrested, saying that one surnamed Xiao and another one surnamed Guo were from Hunan while a third, surnamed Zhao, was from Hubei.
The arrests are believed to be part of a crackdown a mainland cybercrime gangs that use hacking as a tool to blackmail companies. They operate in Changsha, Chengde and Shaoyang in Hunan as well as in Hubei and Shanghai.
The exchange, which was set up in 1910, trades gold contracts with physical delivery services. It has 172 members, mostly jewellery manufacturers and banks.