Authorities from Austria, the Czech Republic, Germany and Sweden also participated in the investigation, it said.
The man was detained in Poland while transporting weapon kits he had purchased in Austria, according to Europol.
It said a subsequent search of the suspect’s home and a nearby forest carried out by Polish investigators uncovered dozens of illegally held firearms, including pistols, rifles, revolvers and automatic weapons, in addition to weapon parts and more than 20,000 pieces of ammunition.
The suspect, a Polish national described as a "high-value target," had previously worked as a licensed firearms dealer, the European police agency said.
Further investigation revealed that the suspect had sold dozens of illegal weapons, including automatic guns and pistols, to criminal networks operating in Germany and Poland, Europol reported.
(gs)
Source: PAP, europol.europa.eu