Ukrainian police have arrested four people suspected of running a network of fraudulent call centers that stole millions of euros from German citizens by luring them into fake cryptocurrency investments.

The arrests come as Kyiv steps up efforts to crack down on illegal call centers, some of which have allegedly operated under the protection of corrupt law enforcement officials.

In a statement Friday, Ukraine's cyber police said the suspects operated call centers across the country, posing as financial advisers and persuading people in the European Union, particularly Germany, to invest in cryptocurrencies and stocks through fraudulent online platforms.

After gaining victims' trust, the scammers helped them open cryptocurrency exchange accounts and transfer funds to wallets controlled by the criminal group. In some cases, they also gained access to victims' online banking accounts.

The stolen funds were then moved through a network of bank accounts and cryptocurrency wallets to conceal their origins before being distributed among members of the group, police said.

Investigators have identified 135 victims in Germany who collectively lost more than €4.3 million ($4.8 million).

Ukrainian authorities conducted two rounds of raids in August and September, searching more than 50 properties in Kyiv and other cities. Officers seized computers, phones, cryptocurrency wallets, documents and more than $90,000 in cash.

The four arrests included the group’s alleged leader.  Three men are being held in pretrial detention, while a suspected co-organizer has been placed under house arrest.

Video released by police showed one suspect hiding on an apartment balcony during a raid, while another attempted to escape.

The suspects face up to 12 years in prison and confiscation of their property if convicted. Investigators are still working to identify other members of the network and additional victims.

Broader crackdown

The arrests come amid a broader push by Ukrainian authorities to combat fraudulent call centers.

In September, Ukraine's parliament approved legislation introducing specific criminal penalties for organizing or operating scam call centers, working at them or recruiting people to participate in fraudulent schemes. The legislation provides for prison sentences of up to 12 years for certain offenses linked to such operations.

The crackdown has also exposed alleged corruption within Ukraine's own security and law enforcement agencies.

Last week, Ukrainian anti-corruption investigators said they had uncovered a criminal organization that allegedly bribed senior officials to protect fraudulent call centers from investigations.

The alleged network involved at least 12 people, including officials from Ukraine's Security Service (SBU), the Prosecutor General's Office and the National Police, as well as individuals linked to organized crime.

Following the investigation, the SBU dismissed two senior officials suspected of involvement in the scheme.