A man in his 60s was taken to hospital with serious head injuries following a collision with a cyclist close to the city centre.
Emergency crews were called to Victoria Road, close to the crossing point near Ladywell Avenue shortly before 5pm on Monday night.
A “large” police presence was on scene, with pictures showing one ambulance in attendance.
A witness said the road was partially closed off heading into the city centre.
He said: “The blue lights were flashing and one of the lanes on the road had been partially shut off as well.
“There was a large police presence and an ambulance on the scene. About five officers were standing around a young man and seemed to be checking his bike.
“I don’t know how he was involved but there were certainly a lot of officers there so it seemed to be a pretty big incident that was ongoing, especially to shut off part of the road at such a busy time of night.”
Xplore Dundee said a number of services, including the 18 and 22 were delayed while police and paramedics remained on the scene.
Police have now launched an appeal to speak to anyone who may have witnessed last the incident.
A force spokesman said: “At around 4.50pm on Monday a pedestrian was involved in a road traffic collision with a cyclist. As a result, the pedestrian suffered a serious head injury.
“As part of the inquiry, Police Scotland is keen to speak to any witnesses, and in particular appeal to the drivers in the area who may have dashcam footage of the incident to contact us.”
A Scottish Ambulance Service spokesman said: “We dispatched one ambulance to the scene and transported one male patient in his 60s to Ninewells Hospital.”