Authorities say two cars collided at 7:55 a.m., at Broadway and West 160th Street.
One of the vehicles then crashed into a 100-foot long scaffolding, leaving it partially collapsed.
One of the critically injured victims and two others who suffered minor injuries were transported to Harlem Hospital.
The other victim was taken to Columbia-Presbyterian Hospital.
Emergency crews are working to stabilize the scaffolding.
CLICK HERE TO SEE PHOTOS FROM SCENE
---
