GUANGZHOU, China — Rivals to Chinese ride-hailing giant Didi are trying to eat away at the company’s market share as it faces a crackdown from regulators.

Days after Didi’s initial public offering earlier this month, Chinese regulators opened a cybersecurity review into the company.

The Cyberspace Administration of China (CAC) also ordered app stores in China to remove Didi from download, alleging the company had illegally collected users’ personal data. No new users are able to sign up.

Last week, authorities ordered a further 25 apps operated by Didi to be removed from app stores.

Didi’s regulatory problems have left the door open for competitors to chip away at the company’s roughly 90% market share.

Last week, food delivery company Meituan re-launched a standalone ride-hailing app that was previously taken off app stores in 2019.

Another rival called T3 plans to expand into 15 cities, according to an internal memo cited by local media. T3 is a venture by three major Chinese automakers, and is backed by technology giants Tencent and Alibaba. The company has been pushing ads on Tencent’s WeChat messaging service, which has over a billion users. Anyone who clicks the ads is offered discount coupons for using the service.

Meanwhile, Cao Cao, a ride-hailing service run by carmaker Geely, is offering hefty discounts for new users on its service.

Didi grew into the dominant player, with nearly 500 million annual active users, through aggressive expansion over the years after buying out Uber’s China business in 2016.

But the company has been caught up in Beijing’s crackdown of its technology companies, particularly as regulators tighten up rules on data security.

Regulators are also tightening their oversight of any Chinese companies that want to list overseas, like Didi. On Saturday, the CAC said any company with the data of more than 1 million users must undergo a security review before carrying out a foreign share listing.