German Gorbuntsov's flat on Byng Street where he was shot outside. Pic: David Anstiss

A former Russian banker is said to be in a “critical but stable” condition and under police guard after he was shot multiple times outside his home in Tower Hamlets on Tuesday.

German Gorbuntsov, 45, was shot several times in a suspected assassination attempt as he entered his multimillion-pound apartment in Byng Street in the Isle of Dogs.

Scotland Yard said it was “too early to speculate” on reports in the Russian press that link the shooting of Gorbuntsov with another murder attempt of the Russian banker, Alexander Antonov, in Moscow in 2009.

Detectives from the Trident Gang Crime Command are dealing with the incident and liaising with overseas counterparts to find the gunman behind the attack.

The suspect, who is white, 6ft and slim, and was wearing dark clothes, was seen running away from Westferry Road after Gorbuntsov was shot.

According to Gorbuntsov’s neighbour, a 54-year-old management consultant who gave his name as John, the gunman “was know” to his victim.

He said: “I arrived home at 6.30pm and went upstairs, and around 9pm that night the police knocked on the door and mentioned there had been an incident, and that someone was critically injured and taken to hospital.

“They mentioned that the attacker was known to the person who’d been attacked.

“The morning after, I came down to go to work just before 7am and the glass here in the door was all smashed in.

“When the police mentioned the incident they hadn’t said it was physically in the foyer,” he added.

Detectives are treating his shooting as attempted murder, but no arrests have been made.