Shaftesbury Square in Belfast city centre has now reopened after a woman was injured in an earlier collision.
A PSNI spokesman said the collision happened at 6.40am. The woman was taken to the Royal Victoria Hospital.
A post from TrafficwatchNI said: "Belfast: The left turn from Dublin Road to Donegall Pass has been reopened following an earlier collision."
Earlier a Northern Ireland Ambulance Service spokesman said: "The Northern Ireland Ambulance Service received a 999 call at 06:36 on Tuesday 11 September 2018 following reports of a road traffic collision involving a pedestrian in Shaftesbury Square, Belfast.
"NIAS despatched one Emergency Ambulance crew to the incident.
"Following assessment and initial treatment at the scene, one patient was transported to the Royal Victoria Hospital."
It is understood the woman was knocked down by a van.
And some hours ago, a post on TrafficwatchNI said: "police have closed the left slip from Dublin Road to Donegall Pass. We are not sure why".
A further post added: "There was an earlier collision involving a pedestrian. Likely to remain closed for some time."