BEIJING, June 14, 2009 (AFP) - Thousands of taxi drivers were on strike Sunday in a large northwest Chinese city over fears that new rules will hit earnings, state media said.

More than 5,500 cab drivers refused to work in the city of Xining, forcing people to walk or use public transport, the Xinhua news agency reported. The strike was triggered Saturday by a report in a local newspaper saying taxi drivers' licences would be valid for only eight years, down from 12.

This led some drivers to fear they would have to pay large amounts of money to their companies to get their licences back, Xinhua said.

The agency cited local officials as saying the drivers had misunderstood the new regulations, although the nature of the confusion was not made clear.

Taxi drivers have emerged as a vocal force in Chinese labour disputes in recent months, sometimes bringing traffic to a near-standstill over issues that have triggered their anger.

Observers have argued that taxi drivers are particularly vulnerable, as they do not enjoy the same job security as many ordinary blue-collar employees.