A JOURNALIST who wrote about a shadowy group of Russian mercenaries operating in Syria has been found dead after apparently falling from the balcony of his apartment.

Russian reporter, Maxim Borodin, died in hospital on Sunday, according to news website Novy Den, where he worked. He fell from the fifth-floor balcony of his flat in Yekaterinburg in unclear circumstances.

Russian media reports claimed police said the apartment was locked from the inside, indicating no one else had entered or left the property.

However Novy Den’s editor said he did not believe the death could have been an accident and he didn’t think Borodin was suicidal, the BBC reports.

Friend Vyacheslav Bashkov, described Mr Borodin as a “principled, honest journalist” and said he had called him at five in the morning last week to claim there was “someone with a weapon on his balcony and people in camouflage and masks on the staircase landing”.

He later phoned back to say the men had been apparently taking part in a security exercise.

Authorities said there are no grounds for launching a case, according to Russian media agency TASS.

“Several versions are being considered, including that this was an unfortunate accident, but there is no sign a crime has been committed,” a spokesman said.

But Harlem Desir, the representative for freedom of the media at the Organisation for Security and Co-operation in Europe said Borodin’s death was “of serious concern”.

“I call on the authorities for a swift and thorough investigation,” he said on Twitter Monday.

In March, Borodin had written about the secretive Wagner group, a mercenary paramilitary organisation that reportedly operates alongside Syrian forces, but has been denied by the Kremlin.

On February 7, the group made headlines when hundreds were killed in Syria in the first open confrontation with US forces in more than 50 years after a manoeuvre took them across the dividing line between US-led and Russian-backed groups.

It’s believed up to 2500 Russian mercenaries work in Syria earning around 300,000 roubles per month as part of the paramilitary force which is reportedly under the control of the GRU, or Russian military intelligence. Many of the people are believed to have worked on Russia’s behalf during the 2014 annexation of Crimea.

The group is reportedly bankrolled by Yevgeny Prigozhin, known as “Putin’s chef” with links to the Kremlin. He was one of 13 Russians indicted in February as a result of Special Counsel Robert Mueller’s investigation on charges he funded the “troll factory” in St Petersburg that allegedly tried to sway the US presidential election in 2016.

The death of Mr Borodin has made headlines in the UK which has recently accused Russia of carrying out an attack Sergei and Yulia Skripal using military-grade nerve agent Novichok.

Russia has denied poisoning the father and daughter and is seeking access to speak to them.

Mr Borodin had also investigated political scandals including those made by a Belarusian escort known as Nastya Rybka in a video posted by Russian opposition leader Alexei Navalny.

Journalists and pro-democracy campaigners have previously been subject to attacks in Russia, with 58 people killed in the country since 1992, according to the Committee for the Protection of Journalists.

Amnesty International’s most recent report said most of the media in country were under state control and used to “smear human rights defenders, political opponents and other dissenting voices.”