People during a candlelit vigil at Trafalgar Square on March 23, 2017 in London, England. Four People were killed in Westminster, London, yesterday in a terrorist attack by 'lone wolf' killer Khalid Masood, 52. Three of the victims have been named as PC Keith Palmer, US tourist Kurt Cochran from Utah and Mother of two Aysha Frade. (Photo by Jay Shaw Baker/NurPhoto via Getty Images)
