Boston Mayor Marty Walsh urged people on Twitter to join in a moment of silence to honour those affected by last year's marathon bombings:
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The Government has previously described the new coin - which enters circulation tomorrow - as "harder to counterfeit than ever before".
The European bloc said that Russia should release hundreds of people it arrested at anti-government protests and rallies.
The singer was coy on which role he would be taking up, going only so far as to say he would not play a stormtrooper.