More than 350 people have been arrested in operations across 28 countries carried out against suspected people traffickers who ferry migrants into Europe, police confirmed on Friday.
European and Turkish police forces carried out the raids and also detained people at a number of border crossings.
The Balkan route is one of the world's most notorious people smuggling passages. People who often started their trips in the Middle East and Africa are taken from Turkey into the Balkans and often on to countries in the European Union.
Most of the 382 people arrested in the raids last month face accusations of migrant, firearms or drug smuggling, Europol said.
Thousands of lorries take the Balkans route into the EU, carrying different goods, including food and construction material.
At the Bulgarian checkpoint of Kapitan Andreevo on the border with Turkey, a migrant was found hidden in the roof of a lorry. About 1,500 lorries enter the EU at the crossing every day.
As well as the arrests, 2 476 attempted illegal entries were detected.
Other European countries also provided criminal intelligence.
In the mass raids, officers seized 106 firearms as well as drugs including cannabis and cocaine, Europol said.
The law enforcement organisation added that multinational criminal organisations source weapons predominantly from the western Balkans, “where human resources with expertise in firearms are widely available”.
The firearms are then trafficked into the EU — mainly to Belgium, France, Germany, the Netherlands and Spain.
Criminal networks are then able to exchange arms for drugs and use weapons “to gain and maintain control over lucrative drug markets”, Europol said.