Investigators have been asked to look into the actions of police after a man was fatally hit by a car on the Mancunian Way.
A man in his 40s was arrested on suspicion of causing death by dangerous driving after the victim, believed to be in his 20s, was struck by a Volkswagen Passat at about 00:50 GMT on Friday.
Greater Manchester Police said it came after they received a report after midnight about a man walking on the road, who they believe was the victim of the collision but could not find.
The force has referred itself to the Independent Office for Police Conduct as a result.
Officers have appealed for anyone with information about what happened to contact them, including those who may have footage of the moments leading up to the incident.
Sgt Andrew Page, from the serious collision investigation unit, said: “We’re committed to carrying out a full investigation into this incident.
“And we want to thank the public for their patience due to the significant delays and disruption on the Mancunian Way.”