Labour leader Ed Miliband's been in the region today, launching his party's local election campaign in Ipswich. He was also due to visit Cambridge and Stevenage but those visits were cancelled following news of the death of Baroness Thatcher.
Malcolm Robertson reports...
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A timeline of exactly what happened.
The car reportedly used as part of a terror attack in Westminster was registered in Chelmsford.
The region's MPs are all thought to be safe after an apparent attack at the Palace of Westminster in London.