BEIJING - Nearly 4,400 suspects were arrested in more than 22,000 cases of economic crimes uncovered across China in March, according to the Ministry of Public Security (MPS) on Sunday.

Liu Jinguo, vice minister of the MPS, said during a nationwide videophone conference that police have uncovered a series of major cases related to underground banks, credit card fraud and tax rebate fraud in Shanghai, Guangdong and Zhejiang. They are now following clues in more than 600 major cases.

The vice minister said police departments will focus on five major fields in their efforts against economic crime: finance, taxation, trade, intellectual property rights, and crimes involving mass participation.

Counterfeit bank cards, bank notes and invoices, pyramid selling and other crimes related to people's livelihoods will be the emphases, said Liu.

He added police will establish a system to reward informants.