In response to the removal of the Uber case study from the InvestHK website, a spokesman said: "There are legal ways in Hong Kong for companies to offer car rental services via mobile applications, but not all mobile car booking applications can meet the legal requirements in Hong Kong.

“As Uber is now being investigated for allegedly operating outside of the legal ambit, as a standard procedure InvestHK has removed the case study from its website."

The agency said it aimed from the outset to ensure the companies it supported are aware of the regulatory regime for their particular business. “It is then the responsibility of the company concerned to ensure regulatory compliance," it added.

Uber’s confidence in Hong Kong had grown, boosted by government aid amid rapid expansion – selecting the city as its regional headquarters for a push into mainland China.

Sam Gellman, Uber’s head of Asia expansion, previously endorsed Hong Kong as “an incredible city, combining global commerce and local culture, large industry and start-up entrepreneurship and innovation”.

“It makes a fantastic regional headquarters for us as we expand in the Greater China area,” he said.

READ MORE: Five Uber drivers arrested in Hong Kong sting on unlicensed car-hailing services

InvestHK previously said it provided Uber with “significant support, including information on public transport and advice on market entry strategy prior to its launch.” It is unclear how much the government-backed support is worth.

“Uber ensures that all rides are covered by insurance, and all drivers on the platform undergo an extensive background check,” Uber said yesterday, without commenting on the arrests.

“We stand by our driver-partners 100 per cent and welcome the opportunity to work closely with the authorities towards updated regulations that put the safety and interests of riders and drivers first,” the company said.

The police operation, codenamed Cellbreaker, comes amid increased pressure from the powerful taxi lobby, which has criticised the government for failing to curb car-hailing apps. It is the latest in a series of conflicts internationally between fast-growing Uber and taxi drivers and cab owners fearful they will lose their business.

Undercover officers yesterday posed as customers and hired cars via the Uber app in Tsim Sha Tsui, Kwun Tong and Sha Tin. The male drivers, aged between 28 and 65, were arrested at their destination in Kowloon City.

The five were being detained for allegedly using a car for hire without a permit and driving without suitable insurance. They were later released on police bail. Five vehicles, including three seven-seater cars, were impounded.

“We are confident that there is sufficient evidence to prosecute the drivers,” said Chief Inspector Bruce Hung Hin-kau of the police traffic unit. “We will seek legal guidance … if there are any problems.”

Officers later raided the office of Uber in Cheung Sha Wan Road and took three male staff away for inquiries, a police source said. The three employees, aged between 25 and 29, were later arrested. A further raid took place at the company’s offices in Sheung Wan later in the day, where computers and documents were seized. 

All have been released on bail to report back to police in mid-September. 

Hung said the investigation was continuing and appealed to the public not to use such services.

As Uber’s global reach has expanded, it has been met by fierce resistance – and sometimes violent opposition.

Mainland Chinese authorities raided Uber’s Guangzhou office in May, accusing the company of offering illegal illicit services.

Street battles erupted across France last month as angry taxi drivers blocked roads, burned tyres and attacked drivers on suspicion of working for Uber. Two company executives were among the arrested, as the government branded its service illegal.

Black cab drivers in London have also shown their opposition to Uber with a “drive slow” protest, leading to gridlocked streets.

Meanwhile, Australian tax officials ordered Uber’s drivers to pay a 10 per cent sales tax, in a bid to bring the US firm into line following complaints.