A Chinese committee has ruled against an employer who fired 40 workers for going on strike, state-media said Wednesday, highlighting rising labour activism in the world's second largest economy.

A manufacturer in the eastern Chinese province of Fujian sacked 40 workers in March for going on strike the previous month, the state run Global Times daily said.

China's ruling Communist Party is wary of an independent labour movement, so only allows one government-linked trade union, which in the past has acted to prevent workers from striking.

But analysts say that in recent years workers have become more empowered as labour shortages turn bargaining power in their favour -- though strikers still risk police detention.

A government labour panel ruled that the dismissals in Fujian were illegal, said the report, citing Chinese media outlet Caixin. It added that the employer would appeal.

It quoted China Institute of Industrial Relations scholar Wang Jiangsong as saying that the ruling "will give other workers and their lawyers confidence as they can view it as a guideline when handling labour dispute cases".

In a separate matter, prosecutors on Monday withdrew a case against factory worker Wu Guijun who was detained for more than a year over a protest in southern Guangdong province, the China Labour Bulletin reported.

The Hong Kong-based NGO estimates that labour disputes have surged 30 percent year-on-year in January-March, thanks partly to a labour shortage and strikers' increased use of social media to organise.

Around 30,000 workers at a Chinese factory run by Taiwanese firm Yue Yuen, which calls itself the world's largest branded footwear manufacturer, in April held one of China's largest strikes in several decades.