China opens an inquiry into Didi, two days after the ride-hailing app’s Wall Street debut.

Two days into Didi’s life as a publicly traded firm on Wall Street, China’s web regulator mentioned new consumer registrations on the Chinese ride-hailing platform can be suspended whereas the authorities performed what they known as a “cybersecurity review” of the firm.

The terse announcement, issued Friday night in China, didn’t clarify what had prompted the assessment nor what it could entail — solely that its goal was “to guard against national data security risks, protect national security and uphold the public interest.”

Didi’s inventory worth fell about 5 p.c on Friday.

The shock intervention by Beijing instantly known as to thoughts final yr’s failed preliminary public providing by Ant Group, the Chinese fintech big, whose share sale in Shanghai and Hong Kong was halted at the 11th hour after regulators summoned firm executives to debate new supervision.

In an emailed assertion, Didi mentioned it could cooperate with the authorities. “We plan to conduct comprehensive examination of cybersecurity risks, and continuously improve on our cybersecurity systems and technology capacities,” the assertion mentioned.

Didi is China’s main ride-hailing app, having bought Uber’s China operations in a 2016 deal that ended a interval of fierce competitors between the two corporations. Didi’s shares started buying and selling on the New York Stock Exchange on Wednesday. The firm says its service had 377 million lively customers in China throughout the yr that resulted in March.

Chinese regulators have been ramping up their scrutiny of the nation’s wider web business since thwarting Ant’s I.P.O., criticizing what they name anticompetitive enterprise practices and insufficient safeguards for customers and their private knowledge.

In April, China’s antitrust authority imposed a landmark $2.eight billion high quality on Alibaba, the e-commerce big. A couple of days later, Didi was considered one of almost three dozen Chinese web companies that have been hauled earlier than regulators and ordered to make sure their compliance with antimonopoly guidelines. Didi promptly issued a press release, which the antitrust regulator printed on its web site, vowing to “promote the development and prosperity of socialist culture and science” and to strictly obey the regulation.

Chinese regulation requires main tech platforms to watch strict requirements in terms of dealing with consumer knowledge.

According to the authorities’s pointers for cybersecurity critiques, officers have 30 enterprise days to finish a preliminary assessment and supply suggestions to regulators, although this may be prolonged by 15 enterprise days in “complex situations.” Regulators then have an additional 15 enterprise days to answer the suggestions.

The web regulator’s announcement on Friday mentioned new consumer sign-ups on Didi can be suspended for the length of the cybersecurity assessment, “to prevent the risks from expanding.”