A serious collision involving a car and a tanker has led to a hazardous chemical spill on the M40 motorway, prompting emergency crews to close the road for safety reasons. The incident occurred at approximately 7:45pm on Monday, November 18, between Oxford and Watlington, affecting the southbound lanes. National Highways reported that emergency services are currently on-site, collaborating with specialist teams to manage the spillage of bitumen from the damaged tanker. A spokesperson for National Highways stated, "Specialist recovery has been arranged and, once on scene, will recover the tanker overnight." In an effort to alleviate traffic congestion, lane three within the closure has been reopened to allow trapped vehicles to exit. However, the main carriageway remains closed due to safety concerns. The spokesperson emphasised the risks associated with bitumen, noting, "Bitumen is hazardous when spilled in large quantities and can damage the road surface." Before the road can be reopened, the chemicals must be fully contained, and the carriageway will need to be inspected for any structural damage. Emergency crews are working diligently to ensure the situation is resolved safely and efficiently.