Up to 16 thousand off-duty police officers are set to march in the capital against cuts to the force. They'll don black caps for every police officer lost under the Government's budget cuts.
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London and the worlds has united on Twitter in defiance of the West minster attack #prayforlondon #wearenotafraid
London was today a city of sirens and half mast flags in the wake of another terror attack.
MPs said they would "carry on" and go to work "as usual" in defiance of the terrorist attack outside the Palace of Westminster.