The R445 is closed to traffic between the Bundle of Sticks roundabout coming out of Naas and Ladytown Crossroads.
Traffic is disrupted in the area and gardaí are asking people to avoid it if possible.
Traffic from Newbridge is being diverted left at Ladytown towards Floods Cross and from the Bundle of Sticks onto the M7 motorway or right onto the Rathangan Road.
According to gardaí, the closure is expected to last for several hours and it is possible that it will be overnight.
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