Chinese authorities have arrested a top public relations executive at Weibo, which is China's largest social media company, on 10 August.

According to an internal memo sent to staff and republished in Chinese media, Mao Taotao, the director of public relations at Weibo, is suspected of bribery and has "seriously harmed the interests of the company".

The memo, whose accuracy was confirmed by a Weibo source, said: "In accordance with company policy and the law, we have decided to fire Mao as punishment and will not re-hire him."

According to the memo, Chinese authorities arrested Mao, who joined Weibo in 2010. It also says that the official soon advanced through the ranks of the marketing and public relations department after his joining.

Additionally, the memo stated that as a long-serving employee and the head of a crucial department, he failed to be a role model and succumbed to temptation, "which fills us with pain and regret".

Earlier this year, a former vice-president of Kuaishou, a Beijing-based video sharing platform, was also arrested for alleged corruption, while Tencent Holdings stated one of its executives was being investigated by the Chinese authorities for "personal corruption" allegations.

Other issues have also engulfed China's technology sector this week. Alibaba Group, which owns Weibo in part, came under fire for delaying action in response to an employee's sexual assault charges against her manager and a client.

The internet watchdog Cyberspace Administration of China (CAC) has summoned Kuaishou, Tencent's messaging service QQ, Alibaba's Taobao and Weibo. It has ordered platforms to remove all the inappropriate content within a given timeline and fined them.

The CAC said: "The operation is focused on solving seven types of prominent online problems that endanger the physical and mental health of minors."

However, as reported earlier this week, Weibo or Sina Weibo, which is also considered as the Twitter of China, has suspended a seven-year-old function that ranks celebrities through fan voting, following the Chinese government's drive to bring order to the country's fan club business.

Aside from the voting feature on Weibo, the platform has been cleared of over 150,000 unpleasant postings, over 4,000 unlawful social media accounts and 814 inappropriate subjects. It was also reported that more than 1,300 "problematic" fan groups had been dissolved, and reality shows have been a target of regulation.

Last week, the Weibo administration account informed that the function grading entertainers, which was first presented in 2014, has been suspended.

As Beijing tightens its hold on the technology industry, China's biggest internet companies have come under increased scrutiny this year.

Shares in Didi Chuxing, a Chinese ride-hailing company, plummeted earlier this month after the CAC ordered internet merchants not to sell Didi's app because it improperly acquired users' personal data.

China's State Administration for Market Regulation (SAMR) said in March that it had punished 12 corporations for ten anti-monopoly deals. Tencent, Baidu, Didi, SoftBank and a ByteDance-backed startup were among the companies, according to the SAMR.

As per local media reports, President Xi Jinping has directed regulators to tighten their grip on internet companies, eliminate monopolies and promote fair competition.