Workers at a Toyota-affiliated parts supplier in north China's Tianjin City continued to strike Friday, the second strike to hit the Japanese auto giant this week.

About 50 workers at the No. 2 plant of Toyoda Gosei (Tianjin) Co. (TG) refused to work Thursday afternoon demanding higher pay, and later about 200 workers, mostly on night shift, walked out,

Workers on the day shift were seen leaving the factory, heading back to their dormitories, at about 10 a.m. Friday.

Some workers told Xinhua that all their colleagues had returned to their dormitories and production was suspended.

They added that workers at the No. 1 plant were also on strike.

The two plants in Dongli Economic Development Area, where more than 30 Toyota suppliers are sited, have more than 1,300 assembly line workers with an average monthly wage of about 1,500 yuan (220 U.S. dollars).

An official at the administrative committee of Dongli Economic Development Area has said on condition of anonymity that local officials and company managers were negotiating with the workers.

Workers planned and called for the strike early June on the Internet. The company had agreed to raise the workers' wages by 17 percent before the strike, the official said.

Usually the company raises wages by 15 percent every year, he added.

TG Tianjin, established in 1995 with a registered capital of 200 million yuan, had an annual sales revenue of 1.53 billion yuan in 2009. Its products range from brake hoses, airbags, instrument panels, to steering wheels.

Another TG subsidiary, Tianjin Star Light Rubber & Plastic Co. (Star Light) in Tianjin's Xiqing Economic Development Area, was hit by a strike Tuesday.

More than 1,000 workers joined the one-day strike, demanding their pay go back up to 2009 levels.

On average, the workers' pay had dropped by 50 percent since early 2010, said a woman employee surnamed Huang.

The workers stopped striking after the company agreed to their demands Tuesday night. The brief walkout had not disrupted Star Light's supply to Toyota's assembly lines in Tianjin, a Tianjin Toyota spokesman surnamed Bi said.

The strikes at TG came after a string of walkouts over pay in China since early May: three at Honda's auto parts plants in Guangdong, one at a parts supplier in eastern China's Jiangsu Province and another at an industrial sewing machine company, also funded by a Japanese investor, in Xi'an, capital city of northwestern China's Shaanxi Province.