Sweeping police raids Monday and Sunday in the area of Amerikis Square in Athens led to the arrest of 28 drug-dealing gang members, all foreign nationals.
The raids were the culmination of a months-long investigation and police said they are looking for another 11 suspects.
The gang, which has been active since the beginning of the year, has been linked to at least 800 transactions with drug addicts.
Police said they would sell narcotics to around 350-400 drug addicts in the area. The arrested suspects were to appear before a prosecutor Monday.