The incident occurred around 4am when a man hung out of a Volkswagen Golf carrying at least four persons and fired as many as eight shots out a back window.

Witnesses thought the shooting was an act of random violence. They said the car contained two men and two women as it drove down Torggata.

One of the men, they reported, leaned out of a back window and fired several shots at shops and buildings on one side of the street. The car then collided with a taxi. Occupants of the Golf then pulled the taxi's driver out of his car and drove off in it.

Police now believe the occupants of the Golf meant to kill the 26-year-old man who was standing outside a kiosk on Torggata at the time. "The shots were fired after those who sat in the car had met the man outside the kiosk," said police spokesman Finn Abrahamsen. "We view this as attempted murder."

The motive for the shooting remained unclear, but Abrahamsen denied it was gang-related.

The damaged taxi was later found in Oslo's eastside Tøyen district around 7:30am. The damaged Golf was found in Christian Krohgs Gate, near the scene of the collision.

Police launched a major search for the occupants of the Golf, who face charges of attempted murder and robbery, among others.