A police car ended up off the A66 near Portinscale, Keswick, on Monday afternoon with airbags deflated.
The incident, opposite the junction where the A66 meets the turn off for Portinscale and Grange, closed the busy road just after 4.30pm.
Police urged motorists to avoid the area because of delays. It is understood the patrol vehicle had been travelling west bound towards Keswick at the time as it approached the junction for Portinscale.
A report on social media from an eyewitness suggested the collision occurred between the police car with its blue lights on and another car.
A spokesman for Cumbria police said: “A Cumbria police patrol car was involved in a collision with a Mini on the A66 near Portinscale just after 4.30pm. There were no serious injuries. The road was closed for some time while the cars involved were recovered.”