Prince William has been spotted selling The Big Issue in London, wearing the magazine's distinctive red vest and a baseball cap.
The Duke of Cambridge was spotted in Westminster by a relative of retired Met Police Chief Superintendent Matthew Gardner, who posted pictures online.
Writing on Linkedin he said: "My brother-in-law was in London today and saw a celebrity, so he took a photo at a distance.
"The celebrity saw the 'covert surveillance' effort and crossed the road to investigate further.
"What an honour to have a private moment with our future king who was humble and working quietly in the background, helping the most needy.
"These 'silent gestures' often go unrecognised."
Below: Prince William meets another surprised passer-by, Vitalijus Zuikauskas, in London
William asked Mr Gardner's brother-in-law if he wanted to buy a copy of the Big Issue, to which he replied "I have no change".
The royal then produced a mobile card machine to complete the successful sale to help support the homeless.
The Big Issue is a magazine focused on social issues, which offers opportunities to people who are homeless or at-risk the opportunity to work as street vendors and earn an income.
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