BRATISLAVA (Reuters) - Slovakia’s public TV and radio broadcaster has come under fire for sacking four reporters last week who had signed an open letter warning of creeping political pressure in state media.

The firings - coming after the murder of an investigative reporter in late February that sparked the largest protests in Slovakia since communism ended in 1989 - have spurred new concerns over media control in the central European country.

The broadcaster RTVS, which is funded by taxpayers, declined in a statement to say why it had sacked the journalists but said it valued freedom of speech and plurality of opinions.

The biggest Slovak opposition party SaS called the RTVS firings “a gamble with public trust”, and a group of academics at Bratislava’s main university and the international group Reporters Without Borders (RSF) also criticized the move.

Slovakia has sought to stand out as the most pro-European in a eurosceptic region and has avoided rule of law disputes with the European Union, unlike Poland or Hungary, where governments have been criticized for tightening their grip over state media.

In their open letter in April, 59 RTVS staff said they “work in a hostile climate... and face pressure to include in their stories people who flirt with disinformation media, lack expertise or have political ambitions”.

They also said new editors who had previously worked as spokespeople for ministries controlled by the ruling coalition parties had not introduced any mechanism to deal with possible conflicts of interest.

The director of RTVS is chosen by parliament. Its current chief, Jaroslav Reznik, came under criticism in his previous job as head of state news agency TASR for signing a deal with Russian news agency Sputnik, which the European Parliament has said is a tool for spreading propaganda and fake news. Sputnik denies the accusations, but Reznik later canceled the contract.

“It is up to the serious media, especially public media, to combat fake news,” Reporters Without Borders said in an emailed statement about the sackings. “We have doubts about Mr. Reznik’s competence to combat fake news.”

RTVS also fired a senior radio editor last month. Three radio reporters quit in protest.

Slovak public anger with the authorities and their failure to tackle graft erupted after the killing of investigative journalist Jan Kuciak, who was shot at home with his fiancee in February by an unknown assailant. Kuciak had reported on graft allegations involving politically connected businessmen.

Weekly protests attracting tens of thousands of people in March led to the resignation of long-serving prime minister Robert Fico, who once called journalists “dirty anti-Slovak prostitutes”.

His three-party coalition remains in power, led by Fico’s former deputy Peter Pellegrini.