A RUSSIAN journalist who investigated the deaths of mercenaries in Syria has died in hospital after falling from his fifth-floor flat.

Maxim Borodin was found injured in the Russian city of Yekaterinburg and later died in hospital.

No suicide note was found and local officials said the incident was unlikely to be the result of criminal activity.

After the journalist was found badly injured at the foot of the building on Thursday, regional authorities said the door of his flat had been locked from the inside, indicating that no-one else had either entered or left the flat.

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However, Mr Borodin told a friend that his flat had been surrounded by security men a day earlier.

Vyacheslav Bashkov said Mr Borodin had contacted him at five o’clock in the morning on April 11 and said there was “someone with a weapon on his balcony and people in camouflage and masks on the staircase landing”.

Mr Borodin had been looking for a lawyer, he explained, although he later called him back saying he was wrong and that the security men had been taking part in an exercise.

The journalist had written about Russian mercenaries known as the “Wagner Group” who were reportedly killed in Syria on February 7 in a confrontation with US forces. The mercenaries were said to be taking part in an attack by pro-Syrian government fighters on the headquarters of a US ally, the Syrian Democratic Forces.

Mr Borodin is the latest in a series of Russian journalists who have recently died in mysterious and unexplained circumstances.

On the same day that he was found injured after the fall, the editor of an official regional newspaper was reportedly assaulted in Yekaterinburg.

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Anna Politkovskaya – one of Russia’s best-known investigative reporters who exposed Russian human rights abuses in Chechnya and produced articles that were highly critical of President Vladimir Putin – was shot dead in a lift at her block of flats in 2006.

In June 2014, five men were sentenced to prison for the murder. However, it is still unclear who ordered or paid for her to be killed.

Journalist Yevgeny Khamaganov died of unexplained causes in Ulan-Ude, Buryatia, on March 10 last year.