The ephedrine, which is also known as 'speed', was meant to be processed into party drug methamphetamine and sent to Malaysia where it is in high demand, besides Thailand, Singapore and South-East Asian countries.
Based on a tip-off, Mohammed Farukh (36) and Fakruddin Ali (25) were intercepted and detained at Itarsi station by NCB sleuths with the help of Government Railway Police (GRP) on February 25.
Their bags were searched and 25 grams of ephedrine was seized from the two men who were travelling on Kerala Express, a top NCB official told PTI.
After interrogating the duo, two people, who supplied the ephedrine to them, have been detained in Delhi, he said.
The police also sprang into action at some locations in Chennai, the official said.
The NCB official said those who have been arrested are being interrogated for their links.
