Police in central China have shut down a hacker training company that taught thousands of people how to launch cyberattacks and provided them with spy software, media reports said Monday.

The reports come amid growing accusations of organised computer hacking originating from China that has chilled ties with the United States, and follow Google's threat last month to quit the Chinese market over cyberattacks.

Police in Hubei province shut down Black Hawk Safety Net and arrested three people, the state-run Xinhua news agency said, calling the operation China's "biggest hacker training website".

The company openly offered downloads of hacker tools and trojan software to 12,000 VIP members and 170,000 others who had registered for free membership.

The Legal Daily newspaper said on its website that the company was shut down in November and that police had frozen more than 1.7 million yuan (250,000 dollars) in assets and confiscated nine web servers, five computers and a car.

Black Hawk Safety Net was founded in 2005 and headquartered in Xuchang city in Henan province which neighbours Hubei.

The China Daily quoted anonymous Black Hawk Safety Net members saying users learned how to hack into the financial accounts of others and steal funds, through courses that cost between 100 and 2,000 yuan.

The reports said authorities began investigating the company last year after finding evidence that three of its customers were involved in a 2007 cyberattack that disrupted web services in the Hubei city of Macheng.

The reports gave no further information on any cyberattacks linked to the company.

Google said in January it would no longer abide by Chinese government censorship and was mulling leaving the country with the world's largest number of online users, citing cyberattacks on it and more than 20 other companies.

Google has said the attacks appeared aimed in part at the email accounts of activists dealing with Chinese human rights issues and appeared to have originated from China.

The Chinese government has denied any involvement in the cyberattacks.

The Google row has added to a tensions between Beijing and Washington on a range of other issues including trade, US arms sales to Taiwan, and Tibet.