A Chechen exile shot dead in a Berlin park had fought against Russian troops and may have been assassinated by a Russian agent. German police arrested a 49-year-old Russian man soon after the shooting on Friday, and found the suspected pistol and bike used in the attack. The victim was Zelimkhan Khangoshvili and he had long been a target. What happened?Witnesses quoted in German media said the killer approached Khangoshvili, aged 40, from behind on a bicycle and shot him twice in the head, then sped off. The attack took place in the Kleiner Tiergarten park in Moabit, central Berlin, just before midday on 23 August. Police were quickly on the scene and arrested the suspected killer, who had been spotted dumping the bike, pistol and other evidence into the nearby River Spree. The gun, a Glock 26, was used with a silencer. Police divers recovered the gun and bike, the Berlin state prosecutor's office tweeted. The suspect, named only as Vadim S, reportedly had a large sum of cash in his flat, searched by investigators. He has been formally accused of "treacherous killing". Vadim S travelled to Berlin from Moscow via Paris a few days before the attack, and had a return ticket to Moscow, German media report. Suspicions fall on Russia partly because of previous high-profile attacks on dissidents abroad. The most notorious in the UK were the poisonings of Russian ex-state security officers Alexander Litvinenko in 2006 and Sergei Skripal in 2018.