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Air pollution reaches high levels in parts of England

2 April 2014 Last updated at 17:13 BST

People shopping in Chelmsford, Essex were experiencing the effects of air pollution which reached high levels in parts of England on Wednesday.

The pollution - a mix of local and European emissions and dust from the Sahara - hit parts of south England, the Midlands and East Anglia.

Defra warned people with health problems to avoid strenuous activity and outside exercise.