Two men from Almere, aged 19 and 22, have been arrested as part of an international investigation into helpdesk fraud, which has led to over 140 arrests worldwide so far.

The probe centred on iSpoof software, which allows fraudsters to pretend to be phoning from a bank or helpdesk and con their victims into handing over large sums of money or giving them direct access to bank accounts.

Dutch police said they came across the software during an investigation into bank helpdesk fraud and discovered that it was hosted by servers in Almere. By tapping the servers, the police were able to monitor software users and their methods.

The tap led to the arrests of the two young men in Almere and helped bring about the closure of the iSpoof service, which was based in London. The iSpoof team were already under investigation by the British police and its founder Teejai Fletcher has been arrested, British police reported.

In total, 142 people have been arrested worldwide and more arrests will follow, Dutch police said. Around 100 of the arrests were in London. Users, there were said to be 59,000 at its height, paid for the service in bitcoin.

Dutch police estimate more than 10 million potential victims were targeted via iSpoof and that the criminals have stolen €50 million in Britain alone.

In the Netherlands, some 20,000 people were targeted via the software.