BEIJING, April 8, 2008 (AFP) - China's aviation watchdog has suspended pilots suspected of carrying out rare industrial action that included a refusal to land planes at scheduled destinations, state press said Tuesday.

Pilots from China Eastern Airlines who were suspected of turning back planes as part of the action in southwest China's Yunnan province last week were suspended pending investigation, the China Daily said.

Two senior airline officials at the company's Yunnan branch were also dismissed, the paper said.

'The Civil Aviation Administration (CAA) of China has ordered China Eastern Airlines to suspend cockpit crew suspected of turning back planes and to step up the investigation and seek the leaders responsible,' the CAA said.

In a statement posted on the administration website Monday it said 18 regional flights in Yunnan took off according to schedule on March 31, but turned back mid-flight ostensibly due to bad weather.

But following preliminary investigations, the CAA found the weather at all destinations in the province was suitable for landing planes.

It was not immediately clear how many pilots were suspended, but cockpit crews usually include three pilots.

China Eastern Airlines was also ordered to compensate passengers who were inconvenienced by the action, it said.

The suspected 'strike action' came after pilots circulated an open letter to China Eastern Airlines calling for improved work conditions, including better pay and working hours, news reports last week said.

It also came after 40 pilots for Shanghai Airlines called in sick at the same time on March 14.

A further 11 pilots of East Star Air disputed working conditions with their company on March 28 causing long delays out of the central China city of Wuhan.

China's domestic pilots have long been clamouring for better pay after pilot shortages led airlines to hire foreign cockpit crews who are paid much higher salaries, reports said.

Industrial action, including strikes, is rare in China, where union activity is strictly controlled by the ruling Communist Party.

Employees in any industry are only allowed to belong to the ruling Communist Party-controlled All China Federation of Trade Unions.