China/TOKYO - A strike at a Honda Motor parts supplier in southern China could augur broader demands across China's vast manufacturing belt as workers seek a bigger piece of the nation's growing economic wealth.

About 100 workers wearing white overalls and blue caps milled about the factory grounds of the Honda Lock plant, a supplier of locks to Honda's car-making operations in China, on Monday after many of the 1,500 workers walked off the job on Wednesday.

The standoff in the gritty factory town of Xiaolan appeared calm, but behind the scenes, holdout strikers spoke of intimidation by officials, surveillance of phone calls and Internet chatrooms, along with a campaign to hire replacements.

Police tracked reporters outside the factory and videotaped proceedings as factory workers streamed out of the factory at the end of the day. Many seemed nervous and wouldn't talk, glancing in the direction of police walking alongside and on motorbikes.

I can't talk to you any more, we are under great pressure, said one. We will likely go back to work and see what happens.

The strike is the latest in a series to hit factories around southern China's Pearl River Delta and a few other regions by workers demanding a greater piece of China's growing economic pie.

The outburst of strikes continues a pattern of recent years that took a pause at the height of the global financial crisis, said Liu Kaiming, executive director of the Institute of Contemporary Observation, a privately funded group in Shenzhen that focuses on labor issues.

We've already seen a growing number of strikes in previous years, especially in 2007 and 2008, when the new labor contract law was introduced, and then there was a gap in 2009, but now we're seeing the trend resume, Liu said.

The Honda strike is an extension of that... It also shows that there is a trend that is being driven by a new generation of migrant workers. They are more willing to speak out about their grievances, and are less tolerant of long hours and tough conditions than the older generation.

The strike at Honda Lock was the third to hit a Honda parts supplier in China in the last few weeks. The other two strikes, at suppliers producing transmissions and exhausts, were settled after workers received pay increases.

Workers at Honda Lock said a senior parliamentary official had tried mediating at the factory on Monday, promising workers a decision on wages would be made on Friday as long as they returned to work before then. Some said that they would, while others pledged to continue the strike.

So far, management at Honda Lock has offered a pay increase of 100 yuan ($15) a month in additional wages and another 100 yuan in allowances, but many workers say that isn't enough in difficult talks that have done little to narrow differences.

Job adverts posted by Honda Lock near the factory offered new recruits an all-inclusive pay package of over 2,000 yuan -- around twice the current level and more than the 1,600 yuan demanded by strikers. A shaven-headed migrant worker reading the notice, however, scoffed: It's impossible. Why would the workers be on strike if wages are already so high?

Honda had previously said production at the Honda Lock plant in the city of Zhongshan re-started on Saturday after three days of stoppage. Some production was running on Monday, but only partially as a number of holdouts had sabotaged operations, said Honda Lock spokesman Hirotoshi Sato.

Guangqi Honda, one of Honda's China car-making joint ventures, was closed on Monday for a public holiday that would run through to Wednesday, said Honda spokeswoman Akemi Ando. Production at Guangqi Honda's two carmaking plants was disrupted last week because of strikes at the other two parts suppliers.

Generally, working conditions at car assembly plants are much better than in other industries, whether we're talking about wages or general treatment, said Wen Xiaoyi, a researcher at the China Institute of Industrial Relations in Beijing.

But conditions at parts suppliers tend to be worse. The reason is car assembly requires mostly skilled workers with some specialized training, but car parts manufacturing is less sophisticated, so workers are less educated and their pay is lower.

(Additional reporting by Chris Buckley in Beijing and Doug Young and Alison Leung in Hong Kong; Editing by Nick Macfie)