Clive Chamberlain from Dorset Police Federation is among those taking part in the march. Officers from every police force in the country are taking part in the protest in London.
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Barry Pring died after celebrating his first wedding anniversary with his wife. His family believe he was killed for his money.
Devon Air Ambulance is warning people about the dangers of using laser pens, after one of its helicopters was targeted on an emergency call.
The parents of a missing man from Weston-super-Mare have made an emotional appeal for him to "come home" after he disappeared ten days ago.