Route 6 westbound traffic had been diverted onto Lexington Avenue during the closure, which lasted more than an hour.
State Police were at the scene investigating the incident which occurred near the entrance to the Cortlandt Town Center.
Three ambulances and several fire trucks responded to the scene.
The extent of any injuries has not yet been reported.
Yorktown Police and Lake Mohegan Fire units assisting with traffic direction.
This is a developing story. Check back to Daily Voice for updates.
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