At least 30 people are dead and scores injured following Tuesday's multiple terror attacks in Brussels.
Belgian media are reporting that at least one suicide bomber was involved in attack on the main international airport and that a Kalashnikov rifle and an undetonated explosive belt was found at the scene.
Chris Phillips, former head of the UK's National Counter Terrorism Security Office says terrorist tactics are constantly evolving...
IN: It does appear...'
OUT:'...prevent that'
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John Gearson - Professor of National Security Studies at Kings College London says the attackers can't be underestimated...
IN: They would have...'
OUT: '...have believed'
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