Allen, who recently released her sophomore album, "It's Not Me, It's You," in the U.S., had recently returned home from a trip to Australia where she had been promoting the release.
The singer was captured wearing electric blue sunglasses and a grey top as she swung at the photographer.
Allen, who regularly addresses issues on her Twitter and MySpace blog, was noticeably silent about the incident on Friday, posting no new Tweets, and only a blog about her upcoming music festival dates.
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