A former Russian banker is in a critical condition in a UK hospital after being shot several times in London.

Scotland Yard detectives are treating the attack on German Gorbuntsov near the Canary Wharf business district as attempted murder.

Mr Gorbuntsov was shot as he entered a block of flats in Byng Street on the Isle of Dogs on Tuesday evening. Police said the suspected gunman, who is white, six feet tall and slim and was wearing dark clothes, was seen running away from Westferry Road.

Scotland Yard said the shooting was not thought to be gang-related or linked to any other incidents in Tower Hamlets, and there have been no arrests. Mr Gorbuntsov’s condition is described as critical but stable. Scotland Yard said it was “too early to speculate” on Russian reports that the attack may be linked to a 2009 investigation into a murder attempt on another Russian banker, Alexander Antonov, in Moscow.

Mr Gorbuntsov, who is in his 40s, previously owned banks in Russia and Moldova. He was returning to his home when the attacker opened fire with a sub-machine gun, the Kommersant newspaper reported.

The apparent attempted assassination will prompt comparisons with the murder of Russian dissident Alexander Litvinenko in London in November 2006.

British prosecutors have named fellow ex-KGB agent Andrei Lugovoy as the main suspect in his poisoning with radioactive polonium-210, but the Russian authorities have repeatedly refused to send him to face trial in the UK.