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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Mild, generally dry and breezy.
The family of a teenager who was stabbed to death as he walked home from college in Chelmsford say they are inconsolable.
Dry and chilly overnight. Winds strengthening Sunday and becoming milder.