Police officers walk outside King Edward VII hospital, central London, Friday.

Police officers walk outside King Edward VII hospital, central London, Friday.

Updated at 11 a.m. ET: A nurse duped by a prank call made to the hospital where Kate, the Duchess of Cambridge, was treated for an extreme form of morning sickness was found dead Friday morning, the hospital said in a statement.

Two Australian DJs, Mel Greig and Michael Christian of Sydney station 2Day FM, pretended to be Queen Elizabeth and Prince Charles and were put through to the ward. They were then given an update on Kate’s health by a nurse.

It wasn't clear what role the nurse found dead Friday played in the incident.

The woman’s body was found at an address in Weymouth Street, London, which is around the corner from King Edward VII Hospital on Beaumont Street. Police described the circumstance of her death as "unexplained."

“It is with very deep sadness that we confirm the tragic death of a member of our nursing staff, Jacintha Saldanha,” said the statement, which was released by the hospital's public relations firm.

Radio DJs impersonate royals, get lowdown on Kate

“Jacintha has worked at the King Edward VII's Hospital for more than four years. She was an excellent nurse and well-respected and popular with all of her colleagues,” it said.

“We can confirm that Jacintha was recently the victim of a hoax call to the hospital. The hospital had been supporting her throughout this difficult time,” it added.

Duke, Duchess 'deeply saddened'

A spokesman for St. James's Palace said that William, the Duke of Cambridge, and Kate were “deeply saddened” by Saldanha's death.

“Their Royal Highnesses were looked after so wonderfully well at all times by everybody at King Edward VII Hospital, and their thoughts and prayers are with Jacintha Saldanha's family, friends and colleagues at this very sad time,” the spokesman added.

John Lofthouse, chief executive at King Edward VII's Hospital, was quoted as saying in the statement that "our thoughts and deepest sympathies at this time are with her family and friends."

Duchess Kate discharged from the hospital

"Everyone is shocked by the loss of a much loved and valued colleague," he added.

Lord Glenarthur, chairman of King Edward VII's Hospital, said Saldanha was "a first-class nurse who cared diligently for hundreds of patients during her time with us."

"She will be greatly missed," he said.

The police and ambulance services said the woman, who they did not name, was dead when they arrived.

“Police were called at approximately 9:35 [a.m. local time, 4:35 a.m. ET] Friday … to reports of a woman found unconscious at an address in Weymouth Street,” a spokeswoman for London’s Metropolitan Police told NBC News.

“London Ambulance Service attended and the woman was pronounced dead at the scene. Inquiries continue to establish the circumstances of the incident,” she added.

The police spokeswoman said the death was being treated as “unexplained” until an autopsy was carried out.

London Ambulance Service told NBC News that they were called to the scene 9:25 a.m. (4:25 a.m. ET].

Two ambulance crews and a duty officer crew went there, but the woman was found to be dead, the ambulance service said.

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