The Chinese government has deleted the popular social media accounts of property mogul Ren Zhiqiang after he publicly criticized President Xi Jinping.

On Sunday, the Cyberspace Administration of China ordered Chinese technology companies Sina and Tencent to shut down Ren's microblog accounts on their platforms.

"Cyberspace is not outside of the law, and no person is allowed to use the Internet to spread illegal information," Jiang Jun, a spokesman for the cyberspace agency, said in a statement.

Ren, who had 37 million followers online, was reported to have posted messages earlier this month saying China's news media must represent and serve the public's interests, not just those of the ruling Communist Party.

His comments, which have since been deleted, came after Xi visited the country's three major state-run news organizations and demanded strict loyalty to the Party.

Related: China censors money transfers on Tiananmen anniversary

Ren is a former chairman of real estate firm Beijing Huayuan and is believed to be well connected in political circles in the capital. He's a member of the Communist Party and served for years on a consultative committee for the Beijing city government.

He has long posted blunt comments online, criticizing everything from property prices to politics. His outspoken stance earned him the nickname "The Cannon."

The Chinese government heavily censors news and information, so it's not uncommon for accounts like Ren's to be shut down, or for people to be arrested for controversial online posts.

But it is rare for the government to issue a statement about a particular case. The cyberspace agency on Sunday didn't specify which of Ren's posts prompted it to act.

CNN was unable to reach Ren for comment on Monday. In a statement issued through social media, local Beijing officials said they would handle his case according to Party disciplinary regulations.

Related: Hundreds arrested as Beijing launches stock market crackdown

The Chinese media sector remains heavily state-controlled, and Western social media platforms such as Facebook (FB) and Twitter (TWTR) are blocked. The country's online censorship program, dubbed the "Great Firewall," often blocks foreign news websites as well.

Under Xi, the government has stepped up censorship, cracking down on dissent and taking a tough stance on outspoken social media users like Ren who command big followings.

The president's visit to the state news organizations earlier this month was widely seen as sending a message that he was taking a firmer grasp of the country's media sector.

It followed the publication by a government agency of strict new guidelines on what can be published online and who can produce such content.

-- Shen Lu contributed to this report