Germany has arrested four members of a gang smuggling narcotics from Iran in an operation that is reported as the country’s largest-ever seizure of heroin. 

Prosecutors said on Friday that police confiscated 700 kilograms (1,543 pounds) of heroin in the port city of Hamburg at the end of August, but the arrests were made overnight on Thursday, September 8, when police searched 10 premises in the eastern cities of Dresden and Chemnitz, as well as in Hamburg and in the Netherlands.

The detainees were an unnamed 35-year-old Iranian in the Netherlands, a 40-year-old Turkish-Serbian suspected ringleader, a 54-year-old German suspected of using his firm's logistics fleet to transport drugs, and a 53-year-old Turkish go-between.

One was detained in Germany, one in Spain, and two others in the Netherlands. Prosecutors are seeking the extraditions of the three who were arrested abroad. 

Last year in September, Indian officials said they had seized nearly three tons of heroin originating from Afghanistan and shipped from Bandar Abbas Port in Iran to Gujarat Mundra port worth an estimated 200 billion rupees ($2.72 billion). More than 2,988 kg of heroin was recovered in one of India's biggest such hauls to date.

In May, Jordan said Iran-backed forces in the Syrian army and militias loyal to Tehran are trying to smuggle hundreds of millions of dollars’ worth of drugs across the Jordanian border to Persian Gulf markets.