Police in southwest China's Yunnan Province have detained six suspects for drug trafficking and seized nearly 57 kg of drugs, local authorities said Wednesday.

Police in Yongping County, Dali Bai Autonomous Prefecture, received a tip-off in April that three vehicles heading to southwest China's Sichuan Province via Dali were suspected of drug trafficking.

On May 21, the police intercepted the vehicles on a highway and captured the suspects. A total of 49.87 kg of methamphetamine and 7 kg of heroin was seized from the vehicles.

Further investigation is underway.

Yunnan is a major front in China's battle against drug crime, as it borders the Golden Triangle known for its rampant drug production and trafficking.