Armed officers from the British Transport Police patrol armed with LMT defender 5.56mm automatic rifles, 9mm Glock pistols and tasers as part of Counter Terrorism Awareness Week at London Bridge station in London on November 27, 2014. British police urged the public to be alert to potential terrorist activity as they said the threat of extremist attacks would last for several years. Launching Counter-Terrorism Awareness Week, police said that even if the violence in Iraq and Syria subsided, the risk of attacks in Britain would continue. AFP PHOTO / JUSTIN TALLIS (Photo credit should read JUSTIN TALLIS/AFP/Getty Images)
