German Gorbuntsov case is likely to be linked to murky world of business and crime, but uncovering truth will not be easy

It was 7.30pm, and German Gorbuntsov was in a taxi on his way back to Canary Wharf. Gorbuntsov, a Russian banker, lived in Byng Street, London E14. The road seemed to have been deliberately chosen for its anonymity: his service apartment faced a row of crumbling brown council flats, and overlooked a shabby garden with an unpromising yukka plant.

Someone was waiting for him in the shadows. After Gorbuntsov stepped from his cab, the hitman opened fire. He shot the Russian four times using a pistol with a silencer. The shooter then fled. He ran down Bellamy Close, and disappeared in a warren of alleys towards Marsh Wall, tossing his weapon – later found by police – in a bush.

Gorbuntsov survived. He remains in a critical condition in hospital. But his shooting is the most high-profile attack on a Russian in London since the 2006 polonium murder of Alexander Litvinenko. It is also a throwback to the 1990s, when rival Russian businessmen typically settled their feuds using bombs and hired killers.

Such assassinations still take place in the Mercedes-choked streets of Moscow – though they are less common than they once were. These days Russian bankers tend to sort out their problems using less physical tactics; after all, the pragmatic reasoning runs, you are unlikely to recover a large debt from someone who has been bumped off.

So Gorbuntsov's attempted murder is unusual. Almost certainly his enemies had his Isle of Dogs hideout under surveillance. The hit demonstrates a sophisticated capacity by foreign criminals to operate in Britain – a country, ironically enough, attractive to rich Russians because it epitomises the rule of law and appears to be secure. (Its other big draw is schools, with Russia's elite privately educating its offspring here.) "He thought he would be safe," his lawyer, Vadim Vedenin, said. "He thought this couldn't happen in London."

"The Russian business world has got much more civilised. Using Chechens and hitmen feels a bit deja vu," Sergey Grechishkin, a Russian asset manager and long-term London resident, said. So why try to kill a Russian banker using old-school methods? "Someone got extremely pissed off with this guy," he said. "It was personal, irritation, something like that. Killing someone doesn't help to get your money back."

Murky world

Gorbuntsov is the former owner of several banks in Russia and Moldova. He fled to London in 2010. The British capital has become the default destination for wealthy Russians in trouble, for good reasons and bad, with the authorities at home. A 45-year-old financier, he was this week preparing to claim political asylum in the UK; his wife, Larisa, is said to be at his hospital bedside. Scotland Yard detectives, meanwhile, have little to go on: they are looking for a hooded gunman, described as white, 6ft tall and slim.

In reality, all clues in the Gorbuntsov case point to Moscow, and to a murky, interconnected world of business, politics and organised crime. Uncovering the truth in this opaque universe is frequently impossible – and often dangerous. "In Russia unfortunately there are usually a number of truths, or levels of truth. This case is a good example," Grechishkin said.

There are motives galore – enough, certainly, to keep detectives from the Met's Trident group busy for months. Gorbuntsov, according to Vedenin, was involved in a bitter dispute with two former business partners. He had recently told Moscow investigators that both men were behind a 2009 attempt to murder another Russian banker, Alexander Antonov. Antonov allegedly owed them $108m. He survived the attack. His son Vladimir owns Portsmouth FC, lives in London, and is currently fighting attempts by Lithuania to extradite him. The Lithuanians accuse Antonov Jr of asset-stripping. Vedenin, a lawyer for Gorbuntsov and the Antonovs, said Scotland Yard had assigned him guards after the attack.

In 2010 two Chechens, Timur Isayev and Aslanbek Dadeyev, were convicted of shooting Antonov, and given long jail terms. The same men carried out another high-profile killing, of Ruslan Yamadayev, an enemy of Chechnya's pro-Moscow president, Ramzan Kadyrov. Yamadayev was gunned down outside the British embassy in Moscow in 2008, as his Mercedes waited at traffic lights.

Investigators from Russia were planning to fly to the UK this week to quiz Gorbuntsov further about the Antonov and Yamadayev cases, his lawyer says. The venue was supposed to be the Russian embassy in Kensington, one source suggests. Their trip was mysteriously cancelled just days before Gorbuntsov was shot, the source added – suggesting someone may have sought to shut down the investigation. And possibly silence Gorbuntsov as well. "Someone didn't want him to give this evidence," Vedenin said.

Most worrying for Scotland Yard is the possible link with Chechnya. Gorbuntsov allegedly told prosecutors that one of his former business partners had approached Adam Delimkhanov for help with recovering the Antonov debt. Delimkhanov is Kadyrov's cousin. He is regarded inside Russia as being extremely dangerous. In 2009 Dubai police accused Delimkhanov of being behind the assassination of another Yamadayev brother, Sulim, in Dubai. US diplomatic cables suggest the Kremlin's Chechen proxies, led by Kadyrov, are behind a string of killings abroad in Austria, Turkey and the Gulf states. Gorbuntsov told prosecutors that his former partners invited the powerful Chechen to at least one meeting in January 2009.

In 2010, meanwhile, Gorbuntsov also claimed he had been forced to sign over $1bn from his Industrial Credit Bank to criminal raiders. The raiders forced his wife, Larisa, to sign over her share in the company – turning up with four members of Moscow's infamous Solneevskaya crime gang. The raiders boasted of their links to Russia's FSB spy agency and to a mafia boss nicknamed "Mad Max". Gorbuntsov wrote dozens of letters to Russian prosecutors, police and the FSB saying he feared for his life, but was ignored, his lawyer says. Soon afterwards Gorbuntsov fled to London, the latest in a long line of refugee businessmen, political exiles and young professionals.

Oligarchs and mobsters

The case exasperates ordinary Russians in London, who say they are tired of being lumped together with oligarchs and mobsters. Konstantin Pinaev, who has lived in the capital for five years and writes the blog Moscowlondon, describes the shooting as "really frustrating". "It's back to square one with the image of Russian migrants," he said. "British people think you are a super-rich nutter. But 99% don't steal money and don't have gazillions in their closets."

Grechishkin agrees. He says that these days the largest group of Russians are respectable, "not very flashy" professionals working in British banks or consulting companies. The exact figure isn't clear – but there are around 300,000 Russians in the UK, with 100,000 in London, he believes. Many are attracted by the UK's favourable tax regime and non-dom status, which means they pay tax only on their British earnings, he added. Of Gorbuntsov he said: "I'd never heard of him. He's not really been on the radar screen in the Russian banking arena."

Indeed, Gorbuntsov's flat in the East End of London was comparatively modest – a luxury service apartment, for sure, but nothing like the Knightsbridge penthouse and country estate favoured by other Russian billionaires settling on the island. The banker may have been less wealthy than was generally assumed. Or, more probably, he was simply trying to keep a low-profile and avoid his shadowy enemies.

Neighbours in Byng Street said crime was a common local feature. Police had sealed the street off for several days while looking for clues. "It's the East End, you know," one resident said. He added: "I wouldn't call it rough. But we had a triad gang who took someone hostage here a few years back. And you have kids who form gangs because there is nothing to do, and the government doesn't help them."

In this case, though, the perpetrators are almost certainly not local. The gunman – most probably from the former Yugoslavia, according to one source – is likely to be far away. And the answers to the mystery lie not in London, bathed in spring sunshine, but in Moscow, still blanketed in heavy snow.