Detectives investigating the shooting of Russian banker German Gorbuntsov near Canary Wharf are trying to trace the taxi-driver they believe picked him up in Bishopsgate the night he was gunned down.

Officers from the Trident Crime Command are treating last Tuesday night’s shooting as attempted murder.

The 54-year-old exile from Moscow was hit several times by pistol fire as he entered his luxury block of flats at Byng Street in Millwall.

Police believe he had arrived by taxi from Bishopsgate, close to Liverpool Street station, where he was picked up at 7pm on Tuesday last week. He was shot half-an-hour later after being dropped off.

The suspect described as white, 6ft tall, slim build, and wearing a dark hooded top, who was seen running away from Westferry Road, through Bellamy Close towards Marsh Wall and into the Canary Wharf district.

Officers now believe the weapon used in the shooting was a pistol, not a sub-machine gun as earlier reported.

Mr Gorbuntsov, who used to own banks in Russia and Moldova, was said by a Moscow newspaper to have been placed in a medically-induced coma and that he was under armed guard in hospital.

Scotland Yard today confirmed he was still in a critical condition, six days after being shot, but was stable.

The Russian press have reported that Mr Gorbuntsov’s lawyer had linked the attack to his role in a 2009 investigation into the attempted murder in Moscow of a banker involving dissident Chechnyans.

An appeal was put out through the East London Advertiser the morning after the shooting for witnesses who may have been in Byng Street at 7.30pm on March 20 to call the incident room on 020-8733 4212, or dial 101 or Crimestoppers anonymously on 0800-555111.

It was the second shooting on the Isle of Dogs in two weeks, after two men were wounded by a shotgun in Manchester Road by the Samuda Estate on March 13, but police are not linking it to last week’s incident.