Slovak police this week detained several suspects in relation to the gruesome murder of journalist Ján Kuciak and his fiancée.

Those detained include several Italian businessmen who were named in Kuciak’s posthumously published reporting as allegedly having links to the notorious ‘Ndrangheta mafia as well as to officials close to Slovak Prime Minister Robert Fico.

Before his death, Kuciak, who worked for the portal Aktuality.sk, had investigated a shady, Italian-run agriculture business in Slovakia together with the Organized Crime and Corruption Reporting Project (OOCRP) and investigative journalism groups in Italy and the Czech Republic. Kuciak’s journalist colleagues have collaborated to publish stories that he was unable to finish.

The murder has sparked a political crisis in Slovakia: The government coalition is wobbling and oppositional anti-corruption protests have taken to the streets. The allies of Prime Minister Fico named in the stories have resigned until the murder investigation is over. Both have denied they had anything to do with Kuciak’s killing. In addition, Slovakia’s culture minister resigned as a gesture to show that the political system in Slovakia had failed.

“We welcome this week’s arrests as a sign of the Slovak government’s seriousness in finding those responsible for the murders of Ján Kuciak and Martina Kušnírová”, International Press Institute (IPI) Deputy Director Scott Griffen said.

“However, it is important to emphasize that these arrests are only a first step in ensuring justice. The authorities must keep up momentum and must leave no stone unturned in locating all who may have been involved in this terrible crime. Even the slightest hint of impunity in this case must be firmly and immediately extinguished.”

Kuciak and his fiancée, Martina Kušnírová, were found murdered on February 25 in their home in Vel’ka Mača, near the capital city of Bratislava. Kuciak was shot in his chest, while Kušnírová, was shot in the head. The police in early statements already suggested that the murders were connected to Kuciak’s work.

In an interview with the The Slovak Spectator, IPI Executive Board member Beata Balogová, editor-in-chief of leading Slovak daily SME, described at atmosphere of “shock” after initial news of the murder.

“Afterwards we realised that the most we can do is just do our job”, she said. “That is why we decided we had to finish Ján Kuciak’s investigation and do our best to come up with the story. This is what we did at Sme. This was also a very strong message that whoever, for whatever reason killed Kuciak, they achieved the complete opposite thing.”