Stricter measures will be taken to monitor emissions and punish violators as the government tries to reduce pollutants from small factories in northern parts of the country, Chen Jining, minister of environmental protection, said on Jan 6.

Large enterprises in the Beijing-Tianjin-Hebei region have been receiving stricter environmental scrutiny, which has resulted in a sharp emissions decline.

However, many small factories are continuing to discharge pollutants, which are partly to blame for the severe smog that recently covered most parts of North China.

It is a challenge for environmental authorities to reduce emissions from those small but highly polluting factories in the region, Chen says.

"We have now put these small polluting factories on our priority list," he says.

By Jan 6, 31 cities in northern and central parts of the country were under red alerts, the highest-level pollution warning, in nearly a week of heavy smog, which has eased since Jan 8.

Measures to reduce the pollution included suspending industrial production and activities at construction sites, and limiting the number of vehicles on the roads.

But inspectors sent by the Ministry of Environmental Protection and local governments have discovered many violations by small factories in Hebei, Henan and Shandong provinces, which continue to ignore production restrictions.

For example, Yusheng, a building materials company in Hebi, Henan province, used its own power generator to restart production after the local government cut its power supply as part of a restrictive move.

The violators will be punished at the upper limit allowed, the ministry said.

Chen, the minister, says the small factories are pursuing profits in disregard of environmental rules, and they can easily restart production without anyone noticing because the authorities are often short of staff.

More remote-sensing and other technologies will be used to cover larger areas. In addition, the public is being encouraged to report violations to environmental officials.

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