BEIJING -- More than 3,500 websites in China have been punished in a campaign against online crimes launched August, the Ministry of Public Security said Sunday.

Police have since investigated more than 4,400 cases, arresting more than 8,900 suspects, busting some 700 criminal gangs and deleting 1.88 million harmful online posts, the ministry said in a statement.

The online crimes include gun-selling, fraud, burglary, hacker attacks, selling of counterfeit products, according to the ministry.

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Major cases illustrated by the ministry include a large gun-selling network in the city of Pingxiang in East China's Jiangxi province, and a cross-provincial criminal gang involved in the theft of over 10 million yuan ($1.58 million) from online banks.

The ministry promised it will step up efforts to create a safe and healthy online environment.