Police investigating the death of a Bradford man who collided with a truck believe he had an altercation with up to five men immediately before he was struck by the vehicle.

Detective Superintendent Chris Thompson today made a fresh appeal for witnesses to the incident on Canal Road, Bradford, at 1.30am yesterday.

He appealed for up to five men in a black car to come forward or for members of the public to identify them.

Det Supt Thompson, of the Homicide and Major Inquiry Team, said: "This is a very tragic incident and we are anxious to establish the full facts."

Police believe the 32-year-old man may have been running away from a group of men when he collided with the recovery vehicle. He suffered serious head injuries and died last night in Leeds General Infirmary.

Police closed off a one-mile stretch of the road following the collision near the junctions with Hillam Road and Sidings Close.

Det Supt Thompson, who is leading the inquiry team, said he believed the dead man was involved in an incident with four to five men in a black car just before he collided with the truck.

"Canal Road is a very busy main artery at any time of the day and there were people and vehicles around," he said.

"There was an altercation with this man and I am keen to establish the nature of this and get to the full facts."

Two men, aged 26 and 17, remain in custody in connection with the incident.

Anyone in the black car or who has any information to help the police should call (01274) 376259.

Anyone with information should contact the police on (01274) 373700 or Crimestoppers anonymously on 0800 555 111. There is also a text message service available for people to send information to - text the word canal followed by your message to 07786 200 806.