A joint operation from authorities in five European nations has resulted in the capture of a smuggling gang that brought upwards of 5,000 illegal Cuban immigrants into the European Union over the past few years.

A statement from Europol on Monday revealed that 62 suspected smugglers were detained in a sting last month who had been operating in Germany, Greece, North Macedonia, Serbia and Spain. Some 25 of the smugglers were Cuban nationals.

They had reportedly specialized in the smuggling of migrants from the Caribbean island using an “unusually long and expensive route,” which saw the new arrivals transported from Cuba to Serbia via Frankfurt airport, before being smuggled into Greece and flown to Spain.