Over 10,000 metric tons of scrap waste imported from overseas was intercepted by customs authorities in Hebei province and shipped out of the country on Dec 1.

The scrap, which was listed as iron ore in the customs declaration, was identified as a blend of substances, including residues from producing minerals, which are banned by the country, according to Shijiazhuang Customs.

In the first 11 months of this year, customs in Hebei verified and rejected 35,300 tons of scrap imported from other countries, it said.

"The imported waste is of great harm, and the ban is helpful for the construction of an ecological civilization," said Xue Lingjun, deputy head of the anti-smuggling bureau of the Shijiazhuang Customs District.

China started restricting and prohibiting the import of some types of solid waste in 1996. It has introduced new bans with expanded prohibited lists since 2017 to prevent environmental pollution brought by the imported waste, according to the General Administration of Customs.

Last year, more than 200 gangs across the country were busted for smuggling prohibited waste, over 700 suspects were arrested and more than 1.55 million tons of solid scrap were identified, including waste plastic, slag and metal, according to the administration.

The country's importation of solid waste, which was used as materials for other products, started in the 1980s.

According to a reform plan for banning foreign waste imports released by the State Council in 2017, by the end of this year all solid waste imports that can be replaced with local materials will be prohibited.

Gao Zhishun contributed to this story.