Four factories in Gongming, Guangming New Area, were shut down and their owners will be fined 100,000 yuan (US$16,330) to 300,000 yuan for discharging polluted water into Maozhou River, a border river between Shenzhen and Dongguan.
Shenzhen's environmental authority also impounded facilities at the four factories, which were operating without licenses.
It was the first time that the environmental authority had acted in accordance with the new environmental protection law to close factories and impound facilities since the law, said to be the strictest of its kind in China's history, took effect Jan. 1.
The factories, located in remote places in an industrial zone in Gongming, were reportedly engaged in metal processing, and discharged wastewater without treating it first.
The environmental authority also took water samples from near the factories. If the water is found to have been seriously polluted, authorities will take legal actions to criminally charge the heads of the factories.