Fireworks have been fired at Buckingham Palace during a protest against austerity. Protesters have gathered at the Queen Victoria Memorial after protesting outside parliament.
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Kurt Cochran and his wife Melissa had been visiting London from the US to celebrate their 25th wedding anniversary and were due to fly home.
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.