LONDON, ENGLAND - MAY 23: The Union flag flies at half mast in Downing Street on May 23, 2017 in London, England. Prime Minister Theresa May has held a COBRA meeting this morning following a suicide attack at Manchester Arena as concert goers were leaving the venue after Ariana Grande had performed. Greater Manchester Police have confirmed the explosion as a terrorist attack with 22 fatalities and 59 injured. (Photo by Carl Court/Getty Images)
