Billionaire Jack Ma's favorite Hong Kong newspaper appears to have become the latest victim of China's crackdown on the media.

The Chinese social media accounts of the South China Morning Post (SCMP) have been suspended, and the media group's news websites were also blocked in China on Thursday.

Alibaba (BABA), the Chinese e-commerce giant founded by Ma, said in December that it was buying the SCMP, Hong Kong's leading English-language newspaper.

The takeover raised fears that mainland Chinese ownership of the paper would result in its reporting becoming more closely aligned with official Beijing views.

With the acquisition still to be completed, it's unclear whether that's how things will play out. But the change in ownership doesn't appear to be affording the newspaper any special treatment inside China.

The accounts of nanzao.com, SCMP's Chinese-language website, were suspended this week on the Twitter-like Weibo (WB) social media platforms run by Sina (SINA) and Tencent (TCEHY). Those accounts had a combined following of more than 1.1 million users late last year, according to the newspaper.

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Its account on WeChat, a platform that allows users to send messages and post status updates, was also blocked.

The reason behind the crackdown wasn't immediately clear.

It could be linked to this week's annual meeting of Chinese legislators, which is typically accompanied by tighter restrictions on the media. The SCMP and the Cyberspace Administration of China didn't respond to repeated requests for comment Thursday.

Just a year ago, the SCMP was celebrating being named as one of the most influential Hong Kong media organizations on Sina Weibo. Now, it appears to have joined other prominent news organizations that have fallen foul of Chinese censors, including The New York Times, Bloomberg and the Wall Street Journal.

"We're really in the midst of a new phase of the crackdown on Weibo," said David Bandurski, a researcher at the China Media Project at Hong Kong University. He noted the recent deletion of the Weibo accounts of outspoken businessman Ren Zhiqiang, who had around 37 million followers.

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Ren ran into trouble with regulators after he criticized President Xi Jinping's call last month for the news media to show strict loyalty to the ruling Communist Party.

"There's no doubt we've seen steadily under Xi Jinping a worsening of the media environment," Bandurski said.

Online media platforms -- many of them operated by private companies like Tencent, Weibo and Alibaba -- are getting particular attention from Communist Party officials, as they can be harder to monitor and censor than traditional media.

"All of these companies have had a close but difficult relationship with the Chinese leadership," Bandurski said.

-- Shen Lu contributed to this report.