Prince William was called to help a man who had been stabbed on Wednesday afternoon (07.09.16).
Prince William and Duchess Catherine
The 33-year-old royal was spotted in the cockpit of an East of England Air Ambulance helicopter at Letchworth, Hertfordshire after responding to a call where a man had been injured after a fight.
Jordan Hamill, 19, who was at the scene, said: "I had just finished work and my friend phoned me and said what had happened and I just ran over there. At first I didn't know it was him, but then everyone kept saying Prince William was there.
"Earlier on there was a crazy lady who ran in front of the helicopter and screamed, 'I love you William' but she got taken away by the police. The police were keeping everyone back but it was cool to be that close.
"At first I didn't know it was him but that's what everyone was saying. It looks like him and everyone was sure it was him. I even heard the police said it was him."
The Duke of Cambridge - who has Prince George, three, and Princess Charlotte, 16 months, with his wife, Duchess Catherine - got out of the helicopter to wave to those who had gathered.
The man who was being treated by paramedics was taken to Lister Hospital by a land ambulance, where he was given treatment for injuries to his arm and back.
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