Chinese web giant Sina will face suspension of its Internet news services if it fails to improve censorship of illegal content, authorities have warned.

The Cyberspace Administration of China (CAC) summoned Sina leaders to a meeting late on Friday over "massive numbers of public complaints about its law violations".

Since the beginning of the year, the administration has received 6,038 complaints about Sina, more than any other web portal. It said the reports indicated that "Sina has spread illegal information related to rumors, violence and terrorism, pornography, swindling, advocation of heresies and has distorted news facts, violated morality and engaged in media hype."

Sina has also published some false news because of hurry and its censorship of user accounts has been poor, undermining online order and damaging public interests, the CAC added.

It asked Sina to correct these oversights and strengthen internal management. If Sina fails to meet these requirements, the CAC will "seriously" punish the firm, with possible measures including a complete shut down of its Internet news services.

Sina's leaders promised they will intensify censorship and publish more information with "positive energy".