The many enemies of the dead Russian banker in London

German Gorbuntsov, a Russian banker with a lot of enemies, had come to London for his own safety.

He had repeatedly told his lawyer he could never return to his homeland. "If I go back to Russia, they will kill me," he had said. In the end, London wasn't far enough away. They - whoever they are - got him anyway.

On Tuesday evening, Mr Gorbuntsov was shot at least four, and as many as six, times as he entered the lobby of a modern apartment building in the shadow of Canary Wharf. Moscow's gangland violence had spread to one of London's quieter streets.

Mr Gorbuntsov collapsed to the floor, blood pouring from wounds to his stomach and chest. A young blonde woman, at first reported to be his wife but now thought to be a very close friend, was at his side as first police and then paramedics battled to save his life.

"There was a lot of blood. The window had been shot out in the door and you could see blood on the walls and on the floor tiles," said Tony Smith, 26, an estate agent who lives in the same block.

Mr Gorbuntsov, 45, who has been a major shareholder of InKredBank and owned Moscow's biggest ice hockey team, had been stripped to his green boxer shorts by paramedics so they could assess his injuries. He lay half across the doormat and half across the grey floor tiles. "He was still alive - I could hear him breathing and groaning," said Mr Smith.

The blonde companion, dressed in jeans and a pink top, was standing beside her friend, at times calm and at times in tears. "She was obviously upset, she was crying," said another witness, Emma Key, 30, "She was trying to get into the ambulance. A policeman was attempting to hold her back."

Mr Gorbuntsov was put into an ambulance, but before it reached the end of the road, it stopped and he was brought outside and given emergency treatment at the side of the road. Armed officers kept watch over his him as paramedics worked frantically to keep him alive.

"There were about eight paramedics working on him and they were surrounded by about four armed police guards," said Mr Smith. "I think he must have died at that point and they were trying to resuscitate him. But because there were so many of them they had to get out of the ambulance to work on him."

Incredibly, Mr Gorbuntsov survived. Last night he was at an unidentified hospital under armed guard, critically ill and in a medically-induced coma. His would-be assassin, described as white, 6ft tall and slim, remained at large.

Detectives charged with tracking down the hitman and whoever hired him were examining CCTV footage and forensic evidence. But they faced an uphill task.

There were several theories as to a motive, involving, in no particular order: armed Chechen gangs; a Russian police investigation into the shooting of Mr Gorbuntsov's business partner; tens of millions missing from Russia's state railway; and allegations of embezzlement and the illegal takeover of a bank in neighbouring Moldova.

"This is still very early days in performing this work," said a Scotland Yard source. "There are a variety of things which could be involved here and the team are trying to pick their way through it, to see which of the many possibilities is the most likely. Hopefully the man who was shot will pull through and, clearly, we will want to talk to him."

Officers will also be interviewing, if they haven't already, Mr Gorbuntsov's wife, Larisa, as well as the blonde woman at his side. According to Mr Gorbuntsov's lawyer, his wife took a plane to London as soon as she heard that her husband had been shot. The couple have a 25-year-old son, Vladislav, who is due in London this week, once he obtains a visa. Intriguingly, Mr Gorbuntsov also has a young child by a woman who, according to his lawyer, is not his wife. It was not clear if this was the companion who was with him when he was shot.

Mrs Gorbuntsova's Facebook page shows pictures of her and her husband looking relaxed and happy on holiday in Prague last August. The banker, a bear of a man, wraps his arm around her as the couple cross the city's Charles bridge. In another photo, they pose in one of the city's squares like typical tourists.

On Sept 4 last year, Mrs Gorbuntsova was positively gushing about her husband. "I never realised that at this age a birthday could be such a wonderful celebration," she posted. "As always, my darling husband arranged the most gorgeous celebration for me. I adore my beloved."

The couple seemed not to have a care in the world. But behind the scenes, his business life, and by implication his wife's too because it is suggested many of his assets are in her name, was in turmoil.

Mr Gorbuntsov made his vast fortune in banking and construction, having started out as something of an enforcer himself. In the 1980s, he was convicted of armed assault and sentenced to three years in jail. Following his release, he set up 40 companies in 15 years in the spheres of security, finance, construction and real estate.

In the cut-throat, wild west world of Russian business, he gained numerous enemies along the way. An early business partner was jailed in 2008 for ordering the murder of an anti-corruption campaigner while Mr Gorbuntsov went from strength to strength.

He owned major shareholdings in banks including InKredBank and Konversbank, the financial institution Interprogress and the construction company Flet I Ko. He was the owner of Moscow's Spartak ice hockey club. In 2008, he became a citizen of Moldova, a state which has been criticised for its standards of adherence to the rule of law, and bought its Universalbank.

But having built up an empire worth as much as several billion pounds, his luck began to run out. His business partner, Alexander Antonov, whose son Vladimir once owned Portsmouth football club, was shot in a Moscow street in 2009.

Mr Antonov survived the attack, for which three Chechen gunmen were convicted, although police never established who had hired them. The same Chechen gang was also convicted of the successful assassination of a Chechen politician and businessman who had challenged the authority of Chechnya's powerful president, Ramzan Kadyrov. In 2010, Mr Gorbuntsov, fearing for his own life, fled to London. In an interview with a Russian news website in October last year, he said, with some prescience: "If I go to Russia I'll be killed or put in prison. I left Russia in 2010 when I understood that it had become dangerous for me to stay there."

It is not clear where he moved to in London. His wife lists an estate agent in Wandsworth, in the south west of the capital, as a Facebook favourite. The apartment block in east London where he was shot was popular for expensive short-term lets but not exactly a suitable residence for a wealthy banker. Nobody recalls seeing the Russian there, opening up the possibility that he was followed to the flats by the hitman, who then seized his opportunity.

According to one report, a black Audi had been seen following Mr Gorbuntsov a week before the attack.

The banker certainly kept his head down and it appears that none of the usual fixers associated with Russians in London had come across him. His low profile could also have been linked to Moldova's decision last year to declare that he was wanted over allegations of large-scale embezzlement. Last week, the Moldovan authorities stepped up their pressure on Mr Gorbuntsov, a prosecutor telling a Russian newspaper: "All the main evidence of his guilt has already been gathered."

One area the police will be examining is how Mr Gorbuntsov fell out with two other business partners, Petr Chuvilin and Sergei Mendeleyev, two former executives of his InKredBank. Last month, Mr Gorbuntsov gave a sworn statement to his Moscow lawyer, Vadim Vedenin, naming Mr Chuvilin and Mr Mendeleyev as the men responsible for Mr Antonov's attempted murder in 2009, allegedly as a way of settling a debt of tens of millions of pounds.

The debt, oddly enough, was said to be owed to Mr Gorbuntsov, who had discussed with the two men how to get the money back but insisted he never sanctioned the subsequent shooting. Mr Antonov has absolved his business partner of any blame.

Mr Antonov told The Sunday Telegraph: "We solved our business dispute normally. I never suspected him in the attack on me. He was often in London and he moved there about a year ago. He does business internationally; I don't know the details. He's a very good, effective developer, he's good in finance. He's a self-sufficient businessman."

He added: "As far as I know, he was leading a happy life, he has a family and he recently had a child." A spokesman for his son, Vladmir Antonov, said: "He is saddened and shocked by this tragic outrage in London. He has contacted both the British and Russian investigating teams and is doing all he can to support their investigations."

Mr Gorbuntsov's statement naming his former associates was passed to Moscow police and prosecutors. On March 2, apparently based only on his statement, the police inquiry into the Antonov shooting was reopened. By October, Mr Gorbuntsov, by then in exile in London, declared: "I have trump cards. According to my information, the law enforcement bodies are working actively on an investigation that will lead to a very high-profile criminal case."

He claimed during the interview that he had lost control of assets equal to $2.5?billion (pounds 1.6?million). In his statement to police, he claimed that Mr Chuvilin and Mr Mendeleyev had "together conceived and realised the attempted murder of Alexander Antonov".

Mr Vedenin said yesterday: "That [testimony] is probably what provoked this shooting." The lawyer said his client had been due to give another statement this week.

The claim is vehemently denied by Mr Chuvilin and Mr Mendeleyev, who have been widely named in the Russian media in relation to the case. Mr Chuvilin, who is said to be living outside Russia, told the Kommersant newspaper that he knew nothing about the shooting on the Isle of Dogs. "I'm distant from all these criminal shoot-outs, because I now live a completely different life," he was quoted as saying. A spokesman for Spartak ice hockey club, of which Mr Mendeleyev is a director, said: "If these accusations had any kind of foundation to them, he would be at the very least under house arrest."

Mr Gorbuntsov made other powerful enemies. The Russian media has scrutinised a financial wrangle with Russian Railways, the state-controlled transport company whose president is Vladimir Yakunin, an ally of president-elect Vladimir Putin.

An estimated $660?million (pounds 415?million) was not repaid after being deposited by Russian Railways into a Moscow bank whose ownership later passed to Capital Trading Bank, another institution controlled by Mr Gorbuntsov and his associates. According to unconfirmed reports, Mr Yakunin was obliged to ask Mr Putin to intervene to retrieve the money. Mr Putin allegedly referred the matter to the FSB, the security and spy agency which he formerly headed.

In October, Mr Gorbuntsov denied he was responsible for Russian Railways' difficulties.

"The money stolen from Russian Railways was taken by the same people who took my business away from me," he said. "At a certain level they called themselves my partners. And up to a certain point I also had illusions about them. Then I realised I was just their latest project."

As Mr Gorbuntsov lay critically ill last night, his wife had still not been allowed to visit him. "Scotland Yard are not telling us anything," complained his lawyer. "I've been in touch with the Russian Embassy in London and they also have no news."

Mrs Gorbuntsova was desperately hoping that "her beloved" pulls through. His enemies will be less keen.