The crimes include hacking, online fraud, illegal sale of personal information, and pornography. The authorities launched a six-month special operation to "clean the internet" amid a crackdown on activists who "abuse" freedom of expression.

Beijing (AsiaNews) – Chinese authorities say police have arrested 15,000 people on suspicion of cybercrime, including hacking, online fraud, illegal sale of personal information, and pornography.

The Ministry of Public Security said on Tuesday that police have investigated more than 7,400 cases of alleged online crimes, leading to the arrests. It did not say when the arrests were made. In most cases, people detained spent a night in jail.

The authorities launched a six-month special operation to "clean the internet" in July, amid a growing crackdown on public dissent.

The ministry said that the special operation had snared suspects who hacked into websites of companies, banks and government agencies.

Some obtained personal information illegally, some altered web information or uploaded content related to online gambling, and some used the internet to defraud others, it said.

China also went after improper online speech, although the ministry's announcement did not list cases involving that.

Xiao Qiang, a professor at the UC Berkeley School of Information in California, told Al Jazeera he had never seen a crackdown on cybercrime at this level in China.

It was possible that some of those arrested could be activists, with cases related to freedom of expression, he said. "The general atmosphere is very tight when it comes to freedom of speech," Xiao explained.

• china
• crackdown
• arrests
• cybercrimes
• dissent