Scotland Yard said three properties - two in Westminster and one in Barnet are being searched along with a number of cars - after two men were arrested on suspicion of terror offences.
Police said that one of the arrests in Westminster took place at a residential address and not near any major landmark.
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The decision represents something of a victory for the president who will now be able to enforce most of his controversial 90-day ban.
Cool in the north, warmer air to the south
Police have warned the drug, known locally as "pink champagne", could be deadly.