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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For some parts of the region, there's a risk of thunderstorms tonight before a mainly fine weekend.
Suffolk fire crews and care home managers have been practicing a major fire at a nursing home near Bury St Edmunds.
Last minute preparations are going on at the church where Princess Charlotte is to be christened on Sunday