Greek police arrested nine people accused of forcing migrants to pay up to 2,500 euros ($3,045) to smuggle them across the border from Turkey. The gang persuaded migrants to walk for up to 10 days after crossing the border before being picked up and taken to a safe house in northern Greece and used violence to make sure they paid for the service, officials said. The migrants were taken by cars to Athens with the gang using sophisticated methods to avoid being caught by police, according to police agency Europol. The gang has been active since 2019 and used more than 130 vehicles for its operations. The leader of the smuggling ring was one of those arrested, Europol said. Northern Greece has become an important centre of migrant-smuggling after Greek authorities, backed by European Union cash, strengthened security along the Evros River that divides Turkey and Greece. Criminal gangs have flocked to the area to try to make money from migrants trying to enter the EU. Last year, the area was the scene of the EU’s most serious migration crisis since 2015 after Turkey said it would no longer uphold a 2016 accord with the bloc to keep refugees on its territory in return for billions of euros in aid. It led to thousands flocking to the borders, and many migrants tried to avoid the bolstered military and police presence by wading across the Evros into Greece.