A pedestrian was killed after being hit by a fire engine reposing to an emergency
Witnesses reported seeing the engine "turned over" near a roundabout in Royston, Hertfordshire, at around 8.45pm on Wednesday.
Another pedestrian was also injured in the accident and was taken to Addenbrooke's Hospital in Cambridge with minor injuries.
Hertfordshire police are investigating the crash but say the circumstances surrounding it were "still unclear".
They confirmed that the pedestrian was killed as the fire engine was responding to an emergency call while negotiating a roundabout.
The fire engine was seen lying on its side in the road which was closed for several hours. It has since reopened.
Nearby resident Andrew Fowler, from Barrington, Cambridgeshire, said: "There's a fire engine turned over. And that's on the second roundabout.
Witnesses reported seeing the engine 'turned over' near a roundabout in Royston
It's a whole mass of blue flashing lights, including ambulance services and another fire engine
"It's a whole mass of blue flashing lights, including ambulance services and another fire engine.
"Apparently it's on the far roundabout from the Tesco's as you come off the 505 at the first roundabout. That is one hell of a piece of equipment to go over."
Alec Hill, a resident in Royston, lives a couple of hundred yards away from the crash.
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Hertfordshire police are investigating the crash but say circumstances are still unclear
She said: "My daughter and I witnessed the scene. We walked by from Tesco and saw the incident and the controls.
"We were sent away from the police. I asked if it was because of injuries, and he said yes.
"It's pretty obvious that if a fire engine goes off on its side then someone's injured.
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"There must have been around 10 to 15 emergency vehicles. We got that far on our walk and were then sent away."
An East of England Ambulance Service spokesman said: "The East of England Ambulance Service dispatched our hazardous area response team (HART), an ambulance officer, ambulance crew, and air ambulance from the East Anglian Air Ambulance (EAAA) charity.
"Sadly a pedestrian has been pronounced dead at the scene whilst a second patient has been taken to Addenbrooke's Hospital with minor injuries."
Another pedestrian was also injured in the accident
A Hertfordshire Constabulary spokeswoman said: "The circumstances surrounding the collision are still unclear, but it appears a fire engine, which was responding to an emergency call, was in collision with a pedestrian whilst negotiating the roundabout.
"The pedestrian suffered fatal injuries and sadly died at the scene.
"The fire engine is currently still in the road and closures are in place at the roundabout and in Rock Road with the junction of Old North Road and the roundabout by the Tesco Superstore."