Allen reported a man named Harry Wilson - who claimed to be a serving soldier - to the Ministry of Defence after he sent her a racist message on the social-networking site.
His tweet read: "All the best with your new family just seen you bought s**t I mean adopted a child from Africa."
The Fear singer was then criticised by a number of Twitter users for reporting Wilson, claiming that the racism allegations depended on whether a comma was intended before or after the word "s**t".
Lily then defended her actions, tweeting: "So let me get this straight it's 'he was just harassing you, not racially harassing you'. Ah, ok then."
She then responded to one user who accused her of "misreading the comment and jumping the gun" by hitting back: "No, his fault for mis-writing more like! IF that's the case, and if it is, then I'm sure his superiors will understand."
However, the mum-of-one has now decided to quit Twitter over the fiasco, announcing: "Ok I'm leaving twitter for a few days,hmmmm maybe hours, we'll see. The stupidity of some people on here is astounding."
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