Anti-narcotics operations conducted in recent months have revealed a number of novel ways that drug smugglers use to try and avoid detection.

Some hid drugs in their bodies, while others used wine or broad bean sauce to conceal the illicit substances.

Police in the Baiyun district of Guangzhou, Guangdong province, recently broke up a drug trafficking gang that had hidden 282 kg of narcotics inside an industrial air compressor and metalworking machine.

Police said the machines looked normal upon first inspection, but the drugs were later revealed through an X-ray scan. Four members of the gang have been detained.

Meanwhile, police in Sheyang, Liaoning province, discovered 16.53 kg of methamphetamine that had been separated into 23 separate packages and hidden inside thick broad bean sauce. The drugs had been sent from Guangzhou to Shenyang using a logistics company.

On May 28, Guangzhou customs stopped a Ugandan man who had hidden drugs inside his body. The man confessed to swallowing 23 compressed capsules of drugs before he boarded his flight in Uganda. He said he could earn $4,000 by acting as a drug mule.

In the 11 days before the Ugandan's detention, an additional eight African drug mules had been stopped by Guangzhou customs.

They were carrying a combined total of 3.9kg of heroin and 4.4kg of cocaine. One of the men, from Nigeria, was said to have hidden ten packages of drugs up his rectum, each described as being the thickness of a baby's arm.

International drugs smugglers have not been confined to using their bodies as a hiding place, however.

On Nov 30, customs staff at Shanghai Pudong Airport scanned five pieces of luggage belonging to a pair of Chinese passengers. Two of the suitcases were found to contain 32 bottles of wine, inside of which was hidden 28.2 kg of cocaine.

The passengers were a couple who did business in Sao Paulo, Brazil. They said a Chinese man had paid them 3,200 yuan ($486) to bring the wine to China. They were detained for further investigation.