A new bypass near Peterborough was closed for five hours yesterday morning (2 November) after four horses ran on to the road, causing a collision with a car.
The car driver escaped injury, but one horse was seriously hurt and was later put down by a vet.
The accident happened on the A16 bypass, which had opened just three weeks ago.
Police say the horses escaped from a nearby field and got on to the bypass at Eye Green at about 2.40am.
The road was closed from 3am to 7.40am while the remaining three horses were rounded up.
A police spokesman told a local paper: “The horses were loose on an isolated stretch of road in the middle of the night.
“Due to it being pitch black at that time of the morning it was difficult for us to round up the animals, so the road was closed off until sunrise to ensure the safety of motorists and the horses.”