Counter-terrorism police are investigating reports of suspect packages being found at army careers offices.
Packages have been found in Canterbury, Oxford, Slough and Brighton, while similar packages were found earlier in the week in Aldershot, Reading and Chatham, the south east counter terrorism unit said.
Police officers consider the situation a "low-level threat" but "viable", sources said.
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Cold and sunny for most, increasingly cloudy from the west. Cloud and wind spreading from the west of UK.