Baidu has not responded to a request for comment about the outage, which affected at least 100 cars.
Labour groups had opposed contractor status, saying it robbed them of rights like sick leave.
Tens of millions of people work in the global gig economy across services like food delivery and transport.
Safety data from US company Lyft says the incidents were reported between 2017 and 2019.
The White House highlights the upcoming offer of free trips in the US by the ride-hailing firms.
The two taxi apps have faced scrutiny for how they handle incidents of sexual assault and other safety issues.
