BEIJING -- The narcotic control authorities from China, Thailand and Vietnam on Thursday jointly cracked a transnational drug manufacturing case, arresting 41 suspects, China's Ministry of Public Security said Friday.

The joint law enforcement operation busted three illegal production labs across the three countries, seizing 6 kg of solid etomidate, 65 liters of liquid etomidate and 15 kg of kratom leaves.

About 5 tonnes of precursor materials and multiple pieces of drug manufacturing equipment were also seized at the scene, the ministry said.

China has long maintained close cooperation with Southeast Asian countries in law enforcement against drug-related crimes.