A Serbian appeals court acquitted four former intelligence officers jailed for the brutal 1999 murder of journalist Slavko Curuvija, a fierce critic of late strongman Slobodan Milosevic.
The decision was quickly condemned by opposition politicians and media rights campaigners.
The ruling overturned their previous convictions in 2021, which saw the group handed lengthy prison sentences.
"The Court of Appeals... finds that the allegations of the accusation have not been proven beyond a doubt," read a statement by the court.
There was no direct or indirect evidence that would reliably confirm that the defendants had carried out the killing, it said.
The decision published on Friday was just the latest in a long, legal process that had already had a number of dramatic twists.
In 2021, a special court sentenced former secret police chief Radomir Markovic and the head of Belgrade's intelligence branch Milan Radonjic to 30 years in prison. Two other intelligence officers were handed 20-year sentences.
An earlier court ruling had found the four guilty in 2019, but that decision had been overturned and a retrial ordered.
- 'Frightening message' -
Curuvija was one of the most critical voices in Serbia in the 1990s, attracting a wide readership as the owner and editor of two leading independent publications.
He was shot 13 times in front of his Belgrade home during the NATO bombing campaign launched in response to the Milosevic government's brutal crackdown on ethnic Albanians in Kosovo in the late 1990s.
His killing came just days after pro-government media outlets had accused him of being a "traitor" and of having called on NATO to bomb Serbia.
On Friday, media groups and opposition parties denounced the court ruling, including the Slavko Curuvija Foundation, a media rights group named after the slain journalist.
"It is a clear sign that the state is not able to deal with the darkest parts of its own services from the '90s, and that they still have a huge influence on both the judiciary and the political processes in Serbia," the foundation said on social media.
The Movement of Free Citizens, a political party in a leading opposition coalition, also condemned the ruling.
It proved the "entire state apparatus and all branches of government are being used to defend the regime of Slobodan Milosevic".
Jelena Curuvija, the slain journalist's daughter, told broadcaster N1 that the ruling was "a clear, frightening message to all journalists".
Paris-based media rights group Reporters Without Borders said they were "devastated" by the acquittal.
"The appeal verdict represents a hard blow to the fight against impunity for crimes on journalists in the Balkans", said Pavol Szalai, head of RSF's European Union-Balkans desk.
And the US ambassador to Serbia, Christopher Hill, also expressed dismay in a post to X, formerly Twitter.
"Disheartening to see that justice and accountability for the killers of Slavko Curuvija remain elusive, even 25 years after his murder," he wrote. "A sad day for journalism."
Journalists have long been targeted in Serbia, where reporters and editors critical of the authorities have been assaulted and intimidated.
Serbian President Aleksandar Vucic, who served as information minister under Milosevic, regularly berates repors during his near-daily public addresses.