The Beijing Government’s cyberspace watchdog is investigating online recruiter Zhipin.com, and truck-hailing apps and Yunmanman, in a crackdown on Chinese tech companies, amid concerns over data security.

The announcement comes a day after the Cyberspace Administration of China (CAC) ordered ride-hailing giant Didi Global to be removed from all Chinese app stores.

Full Truck Alliance, the owner of Zhipin.com, went public in the US stock market last month.

The three app-based businesses have been told to halt new user registrations as CAC probes possible national data security risks.

Full Truck Alliance, also dubbed Uber for trucks, has more than 10 million registered truck drivers and more than five million truck owners on its platform.

Zhipin.com, which connects job seekers and employers, is China’s biggest online recruiter with 24.9 million monthly active users.