A Chinese restaurant owner wanted customers to return to eat his noodles so badly that he tried to hook them by secretly sprinkling in some opium. The man, only known as Zhang, admitted to adding the opium powder to the noodles in his Yan’an restaurant in the Shaanxi province of China and was detained ten days.

Zhang said that last month, he bought two kilograms of poppy buds for 600 yuan, which is equivalent to about $98. He crushed the buds into a fine powder and added them to the noodles he served in an attempt to compel his customers to return.

Authorities said that the opium seeds contained enough opiate drugs to accumulate in the customers’ bodies to a point to cause dependence and produce positive drug tests. Police discovered the additive after stopping 26-year-old Liu Juyou for drug testing at a routine traffic stop. He tested positive and had eaten the noodles shortly beforehand.

The main was detained for 15 days before his family members consumed the noodles and submitted drug test results showing the presence of opiates. The police then linked the positive tests to the noodles.

Opium is a dried latex derived from opium poppy. Opium contains morphine that can be converted to heroin. Opium also contains other opiates that together make the plant derivative highly addictive.

Food in China has been laced with drugs in the past, as indicated by similar cases in 2010 and 2012. Poppy seeds were common in Chinese hot pot sauce until they were banned.