Dozen detained in Singapore-owned plant strike in Shanghai

Workers from Hi-P International, who are on strike, stand next to the fence after police entered the factory with trucks to remove heavy machinery, at a suburban area of Shanghai December 6, 2011.

SHANGHAI (Reuters) - Chinese police detained around a dozen workers at a Singapore-owned electronics plant in Shanghai on Tuesday as a strike involving over 200 workers extended into its seventh day in the latest labour unrest to hit the country.

Around 80 workers also submitted a petition to local authorities, seeking intervention against what they said was a management plan for mass layoffs.

Strikes in China this year have pitted workers frustrated about rising costs against companies struggling with an external economic slowdown. The ruling Communist Party fears public discontent could erode its authority and alarm investors.

"This hurts me so much. I have worked hard for them. They are contravening labour law by asking us to leave but not pay us any compensation. Why are the authorities siding with them? Who can help us weak workers?" a female factory worker, who only gave her surname as Wang, said.

Around a dozen workers at the factory owned by Hi-P International (HIPI.SI) were detained on Tuesday after they knelt down at the main gate, blocking the shipment of heavy equipment being removed from the factory that began earlier in the day, workers said.

The workers first stopped work last Wednesday, denouncing what they said was a plan to relocate the plant to a Shanghai suburb and demanding compensation for layoffs. Workers have said the company planned to hire new staff.

On Tuesday police stepped up its presence around the factory, cordoning off some roads, as blue-jacketed workers held banners demanding management explanations.

Hi-P, whose shares were trading up 2.4 percent on Tuesday, is an electronics contract manufacturer whose customers include Apple (AAPL.O) and BlackBerry maker Research in Motion RIM.TO, according to media and analyst reports.

Hi-P could not be immediately reached for comment. The firm has denied firing workers, saying it was in talks "with the support of the authorities and the labour union".

In factory towns across the export powerhouse of the Pearl River Delta, strikes have been triggered by a cycle of slowing orders from the West and pressure for pay rises.

Thousands of striking workers have crippled production for Western brands at shoe and bra factories in Guangdong province and watch, sport and electronics plants to the south and west.

Stoppages disrupted production last year for automakers, including Toyota and Honda, exposing the demands of 150 million migrant workers. Many provinces boosted minimum wages.

But businesses struggling with razor-thin profit margins, may have difficulty increasing pay this year.

(Reporting by Royston Chan; Writing by Kazunori Takada; Editing by Nick Macfie)