• The fuel, originating in Latvia, Poland, Slovakia, Hungary and Lithuania, was mixed with other components and declared as oil and lubricant to avoid regulations and tax payments.

• Eighteen people have been arrested and another 14 investigated, while 40 companies have been linked to the criminal network.

• Fraudulent marketing causes economic losses, and irregularities generate environmental risks and potential harm to consumers due to damage to the engines of private vehicles.

September 26, 2025.- The Tax Agency's Customs Surveillance Service and the Civil Guard have dismantled a criminal organization that was smuggling adulterated fuel into low-cost gas stations in the Levant to evade controls and tax payments. As a result of the investigation, dubbed Operation Tenk, 18 people have been arrested and 14 others investigated, while 40 companies have been linked to the criminal network.

The investigation began in 2023, following complaints from residents of the town of La Hoya del Campo, in Abarán (Murcia), about the continuous movement of tanker trucks. Thanks to this, the Civil Guard located an irregular gas station.

The search of the establishment resulted in the seizure of more than 70,000 liters of diesel, along with machinery and tanks. It was discovered that this fuel was known as 'designer fuel,' a mixture of diesel and other components added to modify the physical characteristics of the original compound and avoid paying taxes. In addition, a substance known as 'triacetin' was found, a product that does not meet the specifications established for automotive diesel.

It was also determined that the end-use of this modified fuel was low-cost service stations in the provinces of Murcia, Almería, Alicante, and Valencia. The following investigations led to the discovery of two more illegal gas stations in the municipalities of Abanilla and Silla (Valencia).

Fuel declared as lubricant to avoid taxes

Investigators discovered that these adulterated fuels originated in Latvia, Poland, Slovakia, Hungary, and Lithuania, among other countries, and that the shipments were declared as oils and lubricants, not diesel. The aim was to avoid the controls and formalities required for the circulation of products subject to the Special Tax on Hydrocarbons in the EU, as well as the accrual of Special Tax, VAT and Corporate Tax.

These fuel blends are fraudulently marketed by criminal organizations, causing economic losses to both European Union Member States and the business sector due to unfair competition.

Furthermore, the gases emitted during combustion can pose a threat to the environment and public health. Irregular storage also creates risks of spillage and can cause harm to the end consumer due to possible damage to the engines of private vehicles.

A complex framework

The investigation, conducted over two years, has led to the identification of the various members of the criminal network and the "ghost" companies with which they operated.

Some of the alleged businessmen would be front men: people in precarious economic situations who were paid to provide their data for the creation of companies and bank accounts. Among these fake businessmen, the presence of Ukrainian, Latvian, French, and Spanish citizens stands out.

During the investigation, a total of 40 companies based in Murcia, Almería, Alicante, Albacete, Barcelona, Valencia, Madrid, Girona, Lérida, and Tarragona have been linked to the criminal network. During the operation, inspectors from the Tax Agency's Customs Surveillance Area in Murcia and Judicial Police specialists from the Civil Guard inspected a total of eleven service stations and businesses.

To date, 18 people have been arrested and 14 others have been investigated as alleged perpetrators of fraud, document falsification, public treasury fraud, Social Security fraud, money laundering, violation of road safety regulations, and membership in a criminal organization.

Of particular note is the indictment of one of the truck drivers for 26 road safety offenses, for driving vehicles with dangerous goods without a valid driver's license.