Bulgarian authorities are under mounting pressure at home and in Brussels to bring to justice those responsible for the brutal killing of the journalist Viktoria Marinova, who was reporting on alleged corruption.

European Commission vice-president, Frans Timmermans, said he was “shocked by the horrendous murder” of Marinova. He tweeted: “Again a courageous journalist falls in the fight for truth and against corruption. Those responsible should be brought to justice immediately by the Bulgarian authorities.”

The German government also condemned the “brutal and dreadful murder” of Marinova and said it was imperative that “there is a fast investigation and that this horrible event will be illuminated as comprehensively as possible.”

As reported by The Guardian, 30-year-old Marinova is the third journalist to be murdered in the European Union in less than a year.

Marinova was found dead in a park in the north Bulgarian city of Ruse on October 6. She had been raped and died of blows to the head and suffocation, according to investigators.

In October 2017, Daphne Caruana Galizia was killed by a car bomb while investigating corruption among Malta’s ruling elite. In February, Ján Kuciak, a Slovakian investigative reporter, 27, and his fiancée, Martina Kušnírová, were shot dead in their home, 40 miles from Bratislava.

The Bulgarian government said it had no evidence that Marinova’s murder was linked to her work. The Bulgarian prime minister, Boyko Borisov, said: “The best criminologists were sent to Ruse, let’s not press them. A large amount of DNA had been obtained.”

According to The Guardian, Marinova was widely known for hosting a TV show that broadcast interviews with reporters from the Bivol website on alleged fraud involving EU funds linked to businessmen and politicians.