DALIAN -- Customs officers in the coastal city of Dalian in Northeast China's Liaoning province intercepted over 300 tonnes of imported solid waste Wednesday.

Customs officers said they checked a batch of imported goods, weighing 306 tonnes, which was declared as soil conditioner on Wednesday. However, eggshells and feathers were found on the surface of the goods, which were suspected to be solid waste.

Samples of the goods had been sent for inspection and were later confirmed as unfinished compost mixed with domestic waste, which falls under banned solid waste in China.

Further investigation of the case is underway.

China began importing solid waste as a source of raw materials in the 1980s and for years has been the world's largest importer.

Given rising public awareness of environmental protection and China's green development drive, the country decided to phase out and halt such imports by the end of 2019.