Police in France and the Netherlands have arrested 23 people suspected of helping to smuggle about 10,000 Kurdish migrants into the UK.
The group is accused of picking up migrants from car parks in France and taking them to the UK in refrigerated lorries and small rubber boats, law enforcement agency Eurojust said.
Migrants were allegedly charged up to €7,000 per person for the journey.
Eurojust said 19 suspects were arrested in France and four in the Netherlands.
The law enforcement agency set up an international investigation team after French authorities spotted suspects using vehicles with Dutch licence plates.
Migrants were picked up from various car parks in France before being taken to the UK, Eurojust said.
Detectives linked migrants’ payments to an illegal hawala banking system in the Netherlands. Hawala is an informal system of money transfer based on trust where no money actually crosses international borders.
Eurojust executed European Arrest Warrants and the 23 suspects were arrested, while five premises were searched.
The law enforcement agency said the criminal network is alleged to have total profits of about €70m (£59.1m).