A strike at a Japanese-owned electronics factory in north China crippled production on Thursday, extending the industrial unrest that has put manufacturers at odds with increasingly assertive workers, according to Reuters. Employees at the Tianjin Mitsumi Electric Co. factory continued a stoppage that began on Tuesday. Handmade banners with workers' demands hung from the factory gate and about 30 workers gathered near an entrance in rain, cheering reporters outside. The factory is owned by Tokyo-listed Mitsumi Electric, a maker of electronics components. "Human traffickers are not welcome" read one banner at the factory gate. "We want a pay rise" and "We want fair treatment" said other banners, some several metres long. Mitsumi Electric said the factory, with over 3,300 employees, had stopped production because "some of its employees demanded higher wages and improved benefits". The company said it was talking with the striking workers, and the "impact of the stoppage is limited at this point." The factory is the latest high-profile target in slow-burning but persistent labour unrest that has hit foreign-owned companies, often left vulnerable by their position in complex supply chains and by a tightening labour market. Over past weeks, striking workers have demanded higher wages from car parts makers and other manufacturers, especially Japanese auto parts companies with operations in the south. Workers, many of them migrants from poor villages, say their wages have not kept up with rising prices or the profits reaped by companies using China as a low-cost production base. "These strikes show that workers feel more confident that the labour market is moving in their favour," said Li Changping, a former Chinese local official who studies rural issues. "Part of it is that they feel left out of the wealth, but another part of it is that they feel they have gained enough from rising wages that they can take a stand, demand a fairer share," said Li, who now works for a non-government organisation with an office in Beijing. Police guarded the Mitsumi plant and stopped reporters from speaking to the workers inside, and empty coaches were parked outside the gate to block filming of the protest, underscoring the sensitivity of the unrest for the Communist Party-run government, wary of challenges to its grip on power. There were no signs of production at the darkened factory, but pelting rain appeared to deter workers from either coming outside or turning up at all. Locals said they saw hundreds of the Mitsumi workers milling around the plant on Wednesday. COMPANIES VULNERABLE Japanese companies, with their usually tight supply chains, appear especially vulnerable to the industrial unrest. But a Chinese plant of U.S. listed Ingersoll-Rand Plc, which makes air conditioning systems, was also recently hit by a strike. It was unclear what level of pay rise the workers were demanding. One earlier told Xinhua he received just 1,500 yuan ($220) a month after working on Saturdays and putting in two hours overtime every working day. "You have to be really willing to work. My daughter left because she was too tired, they work more than ten hours there," said the mother of one former employee, who like many of the plants' workers, lives nearby. China's domestic media have been largely mute about the strikes, apparently due to state censorship. But Xinhua has issued reports about the unrest on its English-language service. Labour costs in China have been rising, partly encouraged by a government that wants to turn farmers and workers into more confident consumers, even as it tries to keep a lid on strikes.