Twitter user Dylan Morris first spotted the change on Monday afternoon, tweeting:
An hour later, Downing Street deleted the picture and replaced it with one of the prime minister actually wearing a poppy, but not before the original photo had been spotted by other people on social media.
The incident was quickly dubbed Poppygate, and the internet reacted in its usual way.
The original photograph of David Cameron was uploaded to Facebook in July and has been used widely in Downing Street publicity materials. A No 10 spokesperson blamed the incident on an “oversight” and said the digitally enhanced picture had now been deleted.
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