BEIJING, June 30 (Xinhua) -- A senior Chinese official said Thursday that public security departments should concentrate more on online crimes.

The police should focus on risk prevention and control, and improve the network governance system, said Meng Jianzhu, head of the Commission for Political and Legal Affairs of the Communist Party of China (CPC) Central Committee.

Meng said Internet security is closely linked with national security and the people's interests, and the police should clamp down on cyber crimes such as online terrorism, drug trafficking and telecom fraud.

Those responsible for online rumors should be punished to safeguard ideological security in cyberspace, said Meng.

Meng highlighted the rule of law in administering cyberspace, and called for better protection of information infrastructure and big data.