BEIJING: Chinese authorities caught nearly 5,400 suspects last year in a crackdown on online pornography and have vowed to strengthen Internet policing.

"Lewd and pornographic content seriously pollutes the online environment, depraves social morals and poisons the physical and psychological health of the masses of young people," the statement said. "It must be firmly controlled."

The ministry said nearly 9,000 pornographic Web sites have been deleted from the Internet and 5,394 suspects captured in 2009, although it did not say how many of them were formally arrested or charged.

It said future efforts would focus on China-based operators of overseas-registered Web sites and companies that provide Internet services, or register domain names or rent virtual space to sites with pornographic content. The ministry also offered rewards to members of the public who provide useful information in?its efforts.

Last year, China backed down from a requirement for new computers to be loaded with a controversial Internet-filtering software known as Green Dam Youth escort after a major outcry from Chinese citizens and computer companies. That software had been introduced as a filter against porn.