Moscow will react if Germany takes action against Russia over the killing of a Georgian national in Berlin last year, the country’s ambassador to Germany said on Thursday, according to a Russian news agency. The report followed an announcement earlier in the day that German prosecutors would file murder charges against a Russian accused of the killing. Tornike K was shot dead in a park in broad daylight on 23 August last year (his last name has been withheld in line with German privacy laws). He was a Georgian citizen of Chechen ethnicity who fought against Russian troops in Chechnya. He had previously survived multiple assassination attempts and continued to receive threats after fleeing to Germany in 2016. On Thursday, federal prosecutors filed charges of murder and a violation of weapons laws in a Berlin district court against a Russian citizen they identified as Vadim K, alias Vadim S (his last name has also been withheld). The prosecutors alleged that at some point before mid-July last year, Russian state agencies tasked him with liquidating the victim. The suspect accepted the assignment, according to the prosecutors’ statement. He either hoped for financial reward or shared the motives of those who tasked him to kill a political opponent and take revenge for his participation in earlier conflicts with Russia. The statement said that the killer approached Tornike K from behind on a bike in the Kleiner Tiergarten park and shot him in the torso with a Glock handgun equipped with a silencer. The victim fell, and the assailant then fatally shot him twice in the head. The suspect was arrested near the scene shortly afterwards and has been in custody ever since. The suspect reached Berlin after travelling from Moscow to Paris on 17 August , using a passport that had been issued by a Russian government office in the name of his alias, then to Warsaw on 20 August before arriving in Germany the day before the killing, the statement continued. The murder case and alleged Russian involvement in the 2015 hacking of the German parliament have weighed on relations between the two countries in recent months. Speaking to reporters in Vienna after the prosecutors’ announcement, the German foreign minister, Heiko Maas, said: “We once again invited the Russian ambassador for a meeting at the foreign ministry today to make our position unmistakably clear again to the Russian side, and the German government expressly reserves the right to take further measures in this case. This is certainly an exceptionally serious matter, and so from the German government’s point of view it is imperative that this matter be cleared up comprehensively by judicial authorities and the courts.” Vladimir Putin’s spokesman, Dmitry Peskov, last year called the allegations of Russian involvement in the killing absolutely groundless. The victim had lived in Germany as an asylum seeker since late 2016. According to German prosecutors, he led an anti-Russian militia in the second Chechen war of 2000-2004, then in 2008 was tasked by the Georgian government with putting together a volunteer unit to defend that country’s South Ossetia region. The unit was never deployed because of peace negotiations between Georgia and Russia. Russian authorities had classified him as a terrorist and accused him of being a member of the Caucasus Emirate extremist organisation, prosecutors said. The case prompted Germany in December to expel two Russian diplomats, citing a lack of cooperation with the investigation of the 23 August killing. Ambassador Sergei Nechayev said accusations that Russia had ordered the killing of the man were groundless and were not supported by the evidence, the Interfax news agency reported. Reuters and AP contributed to this report.