Croatian police on Saturday completed a comprehensive months-long investigation against 23 suspects who had allegedly formed a criminal organisation to commit various crimes, the Ministry of the Interior said in a statement.

It is suspected that they have smuggled at least 15.7 tonnes of marijuana into Croatia in the last three years, making at least €11 million in illegal profits which they split among themselves.

According to the statement, two chief suspects, identified only as a 37-year-old man and a 35-year-old man, set up an organised crime ring in Croatia and Bosnia and Herzegovina between September 2016 and June 2019, linking up at least seven people.

They allegedly bought marijuana from illegal producers and smugglers in Albania and Montenegro and transported it to the Ljubuski area in southern Bosnia and Herzegovina from where one of the suspects smuggled it into Croatia.

The drugs were then allegedly dispatched to Zagreb and sold to other suspects who then supplied it to the end users.

Between December 2017 and the end of June 2019, the three main suspects allegedly formed a group of at least six persons in Zagreb who intimidated and physically attacked people and set their cars on fire.

Police said that by using violence the suspects tried to enforce debt payments.

Twenty of the suspects are treated as members of a criminal organisation. Five of them are already in investigative custody or serving their prison terms, while the other 15 have been detained.

The investigation also covered three more persons, two of whom have committed crimes but did not operate within this criminal group, while one was cleared of suspicion.

The police said that 150 officers were involved in the investigation, conducting 34 property searches and 25 vehicle searches.

During property searches in Croatia, police seized 6.3 kilograms of marijuana, 25 grams of speed, marijuana plants, seven digital scales, two brass knuckles, a rubber truncheon, a baseball bat, an automatic rifle, two rifles, two pistols, two hand grenades, 112 bullets, 25,500 euros, 19,300 kuna, mobile phones, SIM cards, laptops, USB sticks and various documents. Also seized were a Mercedes S 63 AMG, a Porsche Cayenne, a BMW 740d and two vessels.

Four rifles, including three automatic ones, were seized during searches of the properties of two suspects who live in Bosnia and Herzegovina.