The Games Maker Choir was set up by a group of enthusiastic Olympic volunteers during the London Games.
University student Victoria Verbi decided to set up a choir within the Olympic Park - and within two days of putting a notice in the volunteer newsletter, she'd gathered a group of more than 200 singers.
After one brief rehearsal, the choir performed at the bandstand in the Olympic Park.
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A 24-year-old man has been arrested on suspicion of murder after the body washed up on the Thames shoreline.
Seven people have now been arrested after a man died from serious head injuries
The 38-year-old officer was on his way home from a night shift when he collapsed. His death is not being treated as suspicious.