BEIJING -- Ministry of Environmental Protection (MEP) Friday criticized ceramic enterprises in North China's Hebei province, for insufficient efforts on pollution control.

An inspection team headed by Vice Minister Zhao Yingmin on Thursday found pollution-treatment devices in ceramic enterprises in Gaoyi County, Hebei, were not operating normally.

Emission from gas generators in these enterprises were uncontrolled, and 25 ceramic enterprises failed to install on-line monitoring devices on desulfurization facilities in Gaoyi, where half of Hebei's ceramic products are made, according to the MEP.

The MEP has ordered the local government to stop these enterprises from polluting activities, and that those who do not refrain from discharging pollutants exceeding government-set limits must be suspended.

The inspection team also found more than 10 limestone factories in Pingshan, another county in Hebei, worked without government approval and were heavily polluting. The ministry instructed the local government to close them down.

The MEP predicted air pollution in the Beijing-Tianjin-Hebei region and neighboring cities would reduce by Saturday thanks to a southbound cold front.