Law enforcement agencies from Germany, Albania, Bosnia-Herzegovina, Kosovo and Lebanon shut down 12 locations responsible for thousands of daily scam calls, authorities reported this week.

During searches of the suspects’ residential and business premises earlier in mid-April, police arrested 21 individuals and seized their data carriers, documents, cash and assets totaling €1 million ($1.08 million), according to a statement by Europol.

A criminal network was responsible for defrauding thousands of victims through fake police calls, investment fraud or romance scams, Europol said. Scam callers posed as victims’ close relatives, bank employees, customer service agents or police officers. 

“Using a variety of manipulation tactics, they would shock and cheat their victims out of their savings,” Europol said.

The fraudsters coordinated their activity, focusing on a different priority in each country: Debt collection fraud was conducted from Bosnia-Herzegovina, online banking fraud calls from Kosovo, investment fraud from Albania and prepaid card fraud in Lebanon.

By listening to the phone line of one of the victims, investigators detected that the telephone numbers used by the perpetrators could be linked to over 28,000 scam calls in only 48 hours.

German law enforcement managed to track the actual conversations emanating from the many call centers in real-time — sometimes monitoring up to 30 conversations of varying lengths simultaneously. The police also reached out to victims to warn about potential scams.

Europol stated that, in total, police officers managed to prevent financial losses for the victims in over eighty percent of the indicted crimes. The potential damage from these calls would have amounted to over €10 million.

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