Prince Philip is "shocked and shaken" but unhurt after the Range River he was driving collided with another vehicle and flipped near Sandringham Estate this morning (NZ time).
The Duke of Edinburgh, 97, was driving but was not injured in the collision, which took place close to the Sandringham Estate in Norfolk, Buckingham Palace confirmed.
Police and ambulance rushed to the scene where two people, neither understood to be the prince, were treated for minor injuries.
The duke returned to Sandringham and was checked by a doctor following the crash.
The royal protection officer assigned to Prince Philip was also uninjured.
Pictures from the crash scene show the Prince's Land Rover flipped on its side following a crash with a black people mover.
The duke's vehicle was pulling out of a driveway onto the A149 motorway when the accident happened.
According to eyewitnesses, the vehicle that the duke was driving overturned.
The eyewitnesses said they helped the duke out of the vehicle. He was conscious but very shocked and shaken.
Speaking with Newstalk ZB, UK Correspondent Phil Dampier told Tim Dower the accident happened just off the estate.
"The Duke turned onto a public road and a car was coming the other way with a couple of people in it."
"Now obviously, I am not going to say who was at fault but in some way shape or form there was a collision and the Range Rover the Duke was in overturned and miraculously he walked away from it."
Dampier said the Duke is uninjured and resting with the Queen but there are questions over his driving.
"Obviously there will be questions asked about whether a 97-year-old, wearing glasses and a hearing aid, should be on public roads."
"He hasn't had a crash like this before and he does drive around the estate quite often and it's perfectly normal and he is actually a very, very good driver. So I don't think there will be a problem there, but obviously, if it turns out he was at fault for this accident on a public road then questions will be asked."
The passengers who were in the other car are said to be okay following the crash.
It is unknown who was at fault for the crash, but Dampier said Prince Philip would likely fess up if he was at fault.
"He will be muttering to himself. He will be the first person to admit if he's made a mistake but I can't see him giving up driving."
A Buckingham Palace statement said: "The Duke of Edinburgh was involved in a road traffic accident with another vehicle this afternoon.
"The Duke was not injured. The accident took place close to the Sandringham Estate. Local police attended the scene."
Police officers secured the crash scene, while an ambulance crew assisted two people with minor injuries.
"The road is not blocked. Recovery has been called and we are at the scene waiting for them to arrive."
Prince Philip, who underwent hip surgery in early 2018, was pictured enjoying a solo spin around Balmoral as recently as September last year.
The elderly husband of Queen Elizabeth has become increasingly frail in his latter year, but is fiercely independent and still drives himself around the royal estates.
As a younger man, he famously owned a former British black cab and used to sneak out for unaccompanied drives around London.
Now officially retired from public duty, the prince was last spotted attending church with the Queen and extended family on August 19th.
The Queen and the prince have been at Sandringham for several days and attended church on Sunday.
PRINCE PHILIP'S RECENT HEALTH WOES
The Duke of Edinburgh, 97, has suffered a string of minor health issues in recent years although he has remained largely mobile and independent, particularly given his advancing years.
Prince Philip most recently prompted speculation surrounding his health when he chose not to join the rest of the Royal Family for the traditional Christmas Day church service at Sandringham.
In response a royal source told Reuters: 'The duke is in perfectly good health, he is just spending the day privately.'
He was last seen at the Queen's annual festive lunch at Buckingham Palace in December.
Prince Philip was hospitalised in April last year and forced to undergo hip replacement surgery, although he has been seen carriage driving a number of times since.
In June 2017 he was admitted at the urging of a doctor after a battle with a bladder infection.
The condition forced Prince Philip into the hospital twice in 2012.
In 2015 Prince Philip sported a badly-bruised eye at a reception to commemorate the 800th anniversary of Magna Carta at Buckingham Palace.
He was also wearing two butterfly stitches on a cut to his right ear.
Buckingham Palace do not comment on the health of the royal family but played down Philip's new facial injury by saying that he was: 'Well enough to attend the event.'