A woman has been taken to hospital after she crashed into a tree.
The crash happened in Green Lane in Oxhey Hall this morning.
Police say they were called at 10.40am, with paramedics and the fire service also attending.
A Peugeot driver was taken to hospital with serious injuries.
A police spokesperson said: "Police were called around 10.40am this morning (Thursday September 10) to reports of a single vehicle road traffic collision in Green Lane, Oxhey Hall.
"Officers, the East of England Ambulance Service and the fire service attended.
"A blue Peugeot 1007 Dolce had left the carriageway and collided with a tree.
"The female driver was taken to hospital with serious injuries.
"Road closures were in place while emergency services worked at the scene and recovery was completed."
All roads reopened shortly before 3pm.
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