Slovakia’s police chief, Tibor Gaspar said that the assassination of journalist Ján Kuciak and of his fiancée Martina Kušnírova “likely have something to do with Kuciak’s investigative activities” of politicians linked to the local mafia.

The two were executed with a single bullet to the heart or head on the evening of February 25 in their house in the town of Velka Maca, 65 kilometers east of Bratislava.

Slovakia had “never faced such an unprecedented attack on a journalist,” Gaspar said.

Kuciak, 27, was working for His last story for the news website, on February 9, looked at suspected tax fraud connected to a luxury apartment complex in Bratislava.

The case around the complex prompted protests last year to demand Interior Minister Robert Kalinak’s resignation over his business dealings with a property developer.

Slovak Prime Minister Robert Fico said if that if that were the case, it would be “an unprecedented attack on freedom of the press and democracy in Slovakia.”

Fico announced his government was offering 1 million euros to anyone who helps the authorities find the people responsible.

Editors of major Slovak media urged the government to take necessary steps to find the people responsible for the slayings and “to create conditions for the safe work of journalists.”

Reporters Without Borders, a watchdog group based in Paris, noted that Kuciak was the second journalist killed in the European Union in five months.

“We call for an investigation in order to establish the exact circumstances of Jan Kuciak’s death, and we demand that the authorities shed all possible light on this case, especially as he and those close to him had been threatened in recent months,” Pauline Ades-Mevel, head of the group’s Europe and Balkans desk, said in a statement.

This is the fifth case of a journalist or journalists being murdered in an EU country in the past ten years. Investigative reporter and blogger Daphne Caruana Galizia was murdered in Malta on 16 October 2017. Seven Charlie Hebdo journalists were massacred in Paris on 7 January 2015. Greek radio station manager Socratis Guiolias was gunned down with an automatic weapon outside his home in 2010. And Croat newspaper editor Ivo Pukanic was killed outside his newspaper by a bomb planted next to his car in 2008.

Slovakia is ranked 17th out of 180 countries in RSF’s 2017 World Press Freedom Index, five places lower than in 2016.