Police have issued an appeal for information following a serious incident close to the Dartford Crossing.
A 59-year old man was arrested by officers after the emergency services were called to the Londonbound carriageway of the A2, just before it joins the A282 towards the QEII Bridge.
It happened on Saturday afternoon at around 2:24pm.
South East Coast Ambulance Service and Kent Police were on scene with officers now looking to hear from witnesses and drivers with dash-cam footage.
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It's after a man in his 80s was badly hurt following a collision with a white Iveco articulated HGV.
He was taken to a hospital in London where is condition has stabalised.
The suspect was taken into custody to be questioned on suspicion of causing serious injury by dangerous driving.
Kent Police has asked anyone who can help with their enquiries to reach out to them using their online portal or to call the appeal line on 01474 366149, quoting reference 14-0802.