Police in Spain have arrested eight people in a Europol-backed operation targeting a counterfeit currency network that investigators believe was responsible for the distribution of large quantities of bogus €50 ($56) banknotes in multiple locations across the country.

The suspects, the majority of whom are said to have been Senegalese nationals, were detained during raids on four properties in Madrid after law enforcement officers intercepted fake bills with a face value of €15,000 in a package addressed to the leader of the network.

Police said the contents of the package, which had arrived in Spain from Italy, was intended to be distributed primarily in Madrid and Barcelona, ​​where members of the organisation employed mules to inject the counterfeit currency into local economies via shops and other businesses.

The investigation that led to the arrest of the suspects was launched back in March when Spanish police learned that a Senegalese national was selling fake banknotes as well as dealing heroin, cocaine and cannabis.

Surveillance of the man led investigators to members of the network, who were found to have been making regular trips to Italy to arrange shipments of the fake banknotes they sold.

After realising the international nature of the conspiracy, police in Spain approached Europol and requested assistance with their investigation into the network’s activities.

In statement, Europol said: “Over 60 police officers were involved in the action day [that led to the suspects’ arrests].

“Europol deployed a mobile office to Madrid, allowing for the real-time crosschecking of the information against the agency’s databases.”

In a separate operation, Spanish police and their counterparts in Colombia have dismantled a clandestine counterfeit euro and US dollar banknote printing press in Bogota.

The investigation resulted in the arrest of two people and the seizure of fakes banknotes with a face value of $20,000, electronic devices, a printer, inks, paper and various other tools used during the counterfeiting process.

Colombian police requested technical and operational support from Spanish investigators and Europol once they had established the network was involved in the production of fake euro notes.

Back in April, police in Spain revealed they had broken up an organised crime gang behind a counterfeit note printing operation that made €7,500 every month.

Operation Malla resulted in the arrest of four people and the seizure of counterfeit currency worth €15,500 during a raid on a property in Tenerife that was used as a base by the gang behind the fake banknote plot.

Police in Portugal have broken up what has been described as Europe’s second-largest dark web counterfeit currency network in an operation backed by Europol.

Officers from the country’s Polícia Judiciária detained five suspects who stand accused of producing bogus banknotes and being members of an organised crime group.

The suspects were held after the discovery of counterfeit currency worth over €1.3 million ($1.43 million) in countries including France, Germany, Spain and Portugal.

As part of the operation that led to the suspect’s arrest, investigators carried out raids on eight residential and business addresses, during which they confiscated 1,833 counterfeit banknotes with a total face value of €69,930.

Several other items were also seized, including equipment and materials used to produce counterfeit currency such as computers, printers, security paper with security thread incorporation, holograms and self-adhesive holographic bands, ultraviolet inks and ink cartridges.

In a statement, Europol said: “Europol supported this operation since the beginning with counterfeit and dark web experts. Several meetings were held at Europol, and intelligence notification packages were issued as well.

“Apart from the financial support, the European law enforcement agency provided the Portuguese authorities with analytical and operational support during the action day.

“One Europol’s analyst was deployed for on-the-spot support with a Mobile Office during the action day.”

News of the arrests comes just days after Interpol held a conference at its headquarters in the French city of Lyon that focussed on counterfeit currency, and specifically the role the dark web plays in facilitating the illicit trade in bogus banknotes.

Delegates also examined new methods being used to tackle fake banknotes, the latest security features and currency authentication tools, the challenges of investigating bogus banknotes produced using inkjet printers, and the structure of fake banknote monitoring systems.

According to Europol, counterfeit currency remains a major law enforcement issue in developed economies, despite the fact that the rise of digital payments has reduced the use of physical cash.

Europe’s law enforcement agency has forecast that organised crime gangs will continue to produce fake banknotes regardless of this, not least because the tools and materials required to manufacture counterfeit currency are becoming easier to obtain on dark web marketplaces.

Back in April, Spanish police announced they had dismantled an organised crime network behind the “most active” counterfeit euro note printing operation that had ever been discovered in the country.

Interpol is holding a conference on counterfeit currency at its global headquarters in France.

The three-day event, which kicked off in Lyon yesterday, is hosting 120 experts from 47 countries, who have gathered to debate and share their knowledge of the latest techniques for identifying bogus banknotes.

Delegates attending the Interpol Conference on Counterfeit Currency, whose number includes professionals from law enforcement agencies, money issuing institutions and representatives from private firms and international organisations, are examining the latest developments in currency counterfeiting, banknote security innovations and counterfeiting case studies.

In addition, attendees will also discuss the growing role the dark web is playing in the counterfeit currency trade, as well as emerging technologies, new methods being used to tackle fake banknotes, and the latest security features and currency authentication tools.

Sessions at the conference will be held on the challenges of investigating bogus banknotes produced using inkjet printers, the structure of national and international counterfeit currency monitoring systems, and the need for legal and operational frameworks to prevent the distribution of industrially produced counterfeit banknote components.

Speaking at the opening of the event, Interpol Director of Organised and Emerging Crime Paul Stanfield said: “Preventing organised criminal networks from sourcing the materials for the production of highly deceptive counterfeit banknotes and other security documents is a challenge for law enforcement.

“The main concern is that unscrupulous manufacturing companies which produce security features such as holograms and watermarked security paper suitable for counterfeiting could be co-opted into providing them to criminals.”

Experts attending the conference will be briefed on Interpol’s Project S-Print initiative, which was established to provide a forum in which global police forces and security printing professionals can share best practice relating to the targeting of the organised gangs behind the counterfeit currency trade, and how to stop them from accessing the equipment required to produce fake banknotes and security documents.

Currently comprised of over 25 firms that work in the security printing space and associated industries, the Project S-Print network offers its members the chance to network with one another, access checks to confirm the authenticity of high security substrates or materials, and participate in a worldwide knowledge-sharing platform that involves the staging of meetings, workshops and conferences.

As part of its efforts to boost global law enforcement agencies’ ability to identify fake banknotes and security documents, Interpol has produced an online course on security document identification, which can be accessed by police forces in all member countries through the organisation’s police communications network.