US-based taxi app provider Uber has been frequently hitting the headlines in recent months for being the target of regulatory crackdowns or lawsuits with regulators and taxi companies in a number of cities outside the US. In China, its offices in Chengdu, capital city of Southwest China's Sichuan province, and Guangzhou, capital city of South China's Guangdong province, have been raided recently by police, and transport, industry and commerce authorities, casting a shadow on its operation in the world's largest consumer market.

According to media reports, regulators seized iPhones and documents from the Uber office for its alleged failure to abide by taxi management rules. The ride-sharing service provider allegedly hires unlicensed private vehicles for business, which is illegal in China.

The seizures have sparked online protests from regular users of Internet-based taxi-hailing services. And the move will pacify unhappy taxi drivers who serve traditional taxi companies.