Following intelligence activities, the forces of the Intelligence Ministry in the province busted the major drug ring in the holy city of Mashhad on Thursday.
A number of narcotics smugglers, including two foreign nationals, were arrested in the operation.
The security forces seized 8 kilograms of illicit drugs, mainly heroin.
Iran, which has a 900-kilometer common border with Afghanistan, has been used as the main conduit for smuggling Afghan drugs to narcotics kingpins in Europe.
Despite high economic and human costs, the Islamic Republic has been actively fighting drug-trafficking over the past three decades.
The country has spent more than $700 million on sealing its borders and preventing the transit of narcotics destined for European, Arab and Central Asian countries.
The war on drug trade originating from Afghanistan has claimed the lives of nearly 4,000 Iranian police officers over the past four decades.