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Frustration with illegal immigrants turned to rage last week when an angry mob attacked a Roma gypsy camp outside [of] Naples.

Sometimes, I see 'of' is not used. Is there any difference?

Thanks!
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Hi,

In a context like this, 'of' is not necessary.

Clive
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To the best of my knowledge, "of" is optional here in both formal and casual usage.

You might try some Googles. (I don't think you'd find "of" in a news report.)

- A.
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Comments  
Thanks, Clive and Avangi. I've seen both versions in news articles. In fact, this is one of them. Maybe it wasn't written by a native speaker. Thanks!
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