Source : ` ` We want to reassure runners , spectators , journalists '' about safety , says event CEO . Organizers of the London Marathon say it will take place as planned Sunday . London mayor says ` ` robust safety measures '' are in place for the race . Tens of thousands of people take part in the race each year , cheered on by many more .
NEW : `` We want to reassure runners , spectators , volunteers '' about safety , says event CEO . Organizers of the London Marathon say it will take place as planned Sunday . London mayor says `` robust security measures '' are in place for the event . Tens of thousands of people take part in the race each year , cheered on by many more .