Hong Kong police have arrested five drivers from Uber in a sting operation and searched its office, media reports said, in the latest blow for the global ride-sharing startup.
Uber has encountered a string of regulatory roadblocks as it grows around the world.
Police in the semi-autonomous southern Chinese city posing as customers rented five private cars through a mobile app today morning and paid by credit card, police said in a statement.
"Upon arriving at the destination, the officers paid with credit cards and then revealed their identities, arresting drivers aged between 28 to 65," the statement said without confirming that the drivers were from Uber.
It said they were held for "illegally driving a car for rental purpose and driving without third-party insurance".
News footage from Cable Television showed police raiding an office which displayed an Uber logo and taking away three people.
The drivers had been providing their services through Uber, Hong Kong Commercial Radio reported.
The company has been operating in Hong Kong for about one year.
"Uber ensures that all rides are covered by insurance, and all drivers on the platform undergo an extensive background check," the company's spokesman Harold Li told AFP, without confirming their drivers were arrested.
Footage showed five vehicles being cordoned off, including BMW and Mercedes Benz sedans.
Uber has faced setbacks around the world as it expands internationally.
An Uber driver in Brazil's financial capital Sao Paulo responded to a call, only to find himself ambushed by a group of regular taxi drivers.
Last month the firm suspended its UberPOP service in France, six months after being banned.
There have been a string of protests against Uber by black cab drivers in London who say it represents unfair competition.
But in New York, city officials last week scrapped plans to cap the number of vehicles operated by Uber.
