In the aftermath of atrocities in France last year, London's most senior police officer warned that an attack was "highly likely" -- a case of "when, not if." Given the threat, it may come as a surprise to people unfamiliar with the British model of policing that fewer than one in 10 London police officers carries a gun in their daily duties. Keith Palmer, the 48-year-old officer stabbed to death at the gates of Parliament, was unarmed. Only a select number of police officers in Britain are trained as firearms specialists; the rest carry tools including batons and stun guns. In London, it's common to see tourists posing with police as they guard the city's landmarks.

Source: CNN March 24, 2017 10:30 UTC