Six people in the U.K. and Netherlands were arrested on charges stemming from the theft of €24 million, $27.3 million, worth of cryptocurrency.

The arrest was carried out by the U.K.’s South West Regional Cyber Crime Unit (SW RCCU) in a joint operation with the Dutch police (Politie), Europol, Eurojust and the UK’s National Crime Agency (NCA) after a 14-month long investigation, according to a 25 press release.

The investigation stemmed from a case of typosquatting in which a well-known online cryptocurrency exchange was spoofed to gain access to victims’ Bitcoin wallets and steal their funds and login details. 

Five men and one woman were arrested in simultaneous warrants this morning at their homes in Charlcombe, Lower Weston and Staverton in the U.K. and Amsterdam and Rotterdam in the Netherlands, the release said. 

The heist is believed to have affected at least 4 000 victims in 12 countries, but more may have been affected.