There is understood to be a 100m cordon in place around Grand Arcade in Cambridge following reports of a suspicious package.
Bomb disposal teams have been dispatched, police are expected to be in the area for several hours.
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The sunshine is here to stay for the time being. Temperatures will reach the mid-20s this weekend but be aware of the high UV levels.
UKIP have made further gains in the local elections in the Anglia region and the Conservatives have won back control in Peterborough.
Hundreds of council workers have gathered in sports centres and town halls across the region to count the votes in the 2016 local elections.