Police in Chongqing have detained eight people for processing bacon illegally to sell for profit, Xinhua News Agency reported.

Officers also found four sites hidden in a market in the municipality's Shapingba district where the eight were processing pork.

Police raided the sites on Jan 28 and seized pork estimated to be worth 500,000 yuan ($80,200) and more than 10 tons of bacon.

Investigations showed the sites were usually closed in the day and only started business at about 6:00 pm every night. The sites were operating without a license from the local industry and commerce bureau and without a health certificate.

One suspect admitted they added Sudan Red, a blacklisted additive harmful to human health, to give the bacon a better appearance, police said.

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