The 43-year-old asylum seeker, a vocal critic of the Chechen Republic's government, has been found dead with gunshot wounds near Austria's capital Vienna.
Austrian police have arrested two Russians from Chechnya over the fatal shooting of a Chechen dissident, officials said, fueling concerns over the security of Chechen government critics living in exile.
The 43-year-old asylum seeker, a vocal critic of the Chechen Republic's government, was found dead with gunshot wounds near the capital Vienna on Saturday.
Police arrested a 47-year-old Russian from Chechnya in the city of Linz, some 200 kilometres from Vienna, shortly after finding the body.
A second Russian, 37, also from Chechnya living in Austria, was detained Sunday for investigations into the murder.
Police and prosecutors said on Monday the crime was still under investigation and it was too early to comment on any motive.
The dead dissident – identified by Russian media as Mamikhan Umarov now using the name Martin Beck – had given evidence in a 2017 murder case in Ukraine, the Ukrainian interior ministry said.
In that case, a gun attack near Kiev, a volunteer soldier, who had been accused of plotting to murder Russian President Vladimir Putin, was injured and his wife killed.
Chechnya is a predominantly Muslim Russian republic in the North Caucasus. Two wars in the 1990s triggered a wave of emigration, with many Chechens heading for western Europe.
But more Chechens have fled into exile in recent years because of disagreements with pro-Kremlin Kadyrov, who activists accuse of repeated rights violations.
Russia's Novaya Gazeta independent newspaper wrote that the murdered man was a "personal foe" of Kadyrov, and his Chechen-language blog was popular because of the "outspokenness of its author".
It said he also gave "detailed evidence" on contract killings of Kadyrov's opponents to the Ukrainian SBU security service and counter-intelligence agencies.
Former populist Ukrainian lawmaker Igor Mosiychuk, who also knew Umarov, wrote on Telegram messenger that the killing was "100 % committed by Russia."
He said Umarov, who he last saw in February, had asked his help with ordering a bullet-proof vest.
The Austria shooting has heightened concern over the security of Chechen dissidents living in exile.
In February, an exiled Chechen blogger also critical of Kadyrov fended off an attacker armed with a hammer.
A month earlier, Chechen opposition leader Imran Aliev was found dead in a hotel room in the northern French city of Lille, stabbed 135 times.
In Austria, Chechen dissident Umar Israilov was shot dead on a Vienna street in 2009.
In 2011 three ethnic Chechen men were convicted in Vienna for the murder.
Umarov, a former policeman who came to Austria in 2005, was one of the witnesses police questioned when investigating the Israilov killing, Austrian media reported.
He was from the same place as Israilov and knew some of the suspects, according to the reports.