The double Olympic champion crossed the line first in today's 3000m race at the Olympic stadium in Stratford.
He won with a time of seven minutes and 36 seconds - a personal best. The latest win comes before he heads to the World Championships in Moscow in August.
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The 6km bike track will include 130m of the South Circular near Kew Bridge.
The unfortunate officer was taken to a central London hospital for treatment and his condition is not life-threatening.
Detectives investigating the Parsons Green terrorist attack have arrested a 17-year-old boy in Thornton Heath, south London.