Chinese authorities have arrested today a top communications director at Chinese social media giant Weibo accused of taking bribes.

Mao Taotao, former senior public relations director at Weibo, was detained by police on suspicion of accepting bribes and committing fraud.

Weibo, part-owned by e-commerce giant Alibaba Groups, said the company had fired Mao and will not re-hire him after he had seriously harmed the company’s interests.

Mao joined Weibo in 2010 and was quickly promoted through the ranks of the marketing and public relations department, the company said.

Nasdaq-listed Weibo has seen stocks tumbled after Mao’s arrest.

Weibo, the Chinese version of Twitter, has recently been under fire in the wake of a scandal involving Chinese-Canadian pop star Kris Wu, who Chinese police last week arrested on allegations of soliciting sex with underage girls.

Wu has denied the allegations.

Following Wu’s arrest, the Chinese state-run People’s Daily criticised social media platforms for making celebrities out of “unworthy individuals” to generate traffic and money.

Weibo later took down its widely used feature “star power list”, which ranked celebrities based on the popularity of their posts and number of followers. The company said the decision was due to “irrational fan support.”

Beijing continues its regulatory crackdown on Chinese billionaire Jack Ma’s Alibaba empire.

Alibaba Group had fired a manager yesterday over suspected sexual assault on another female employee.

The group also announced policies to prevent sexual harassment in the office but was criticised by state media for no action until the accuser went public.