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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Very cold with snow showers and significant wind chill. Temperatures dropping to -3 deg C (27 F)
Tributes have been paid to a 25-year-old man from Essex who was found dead in a river in "unexplained" circumstances.
Feeling very cold and mostly sunny today with some snow showers overnight. Top temperatures reaching only 2 deg C (36 deg F)