According to multiple reports the owner of a restaurant in China has confessed to mixing his noodle dishes with opium to keep customers coming back.

This was revealed when customer Liu Juyou tested positive for opium following a traffic stop, the BBC has reported.

Liu insisted that he had never taken drugs and suspected the noodle shop in question, the Xi'an Evening News reported, according to the BBC.

To prove his innocence, Liu convinced his family members to eat the same noodles, then test themselves for drugs. His family members came back as positive. 

The restaurant's owner admitted to police that he purchased 4.4 pounds of poppy buds for $100 in August, and had been grinding them into a powder that he added to the noodles.