The starting pistol has been fired for the elite men's race in the Great North Run.
Mo Farah is taking part.
More top news
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.