Smog over Paris
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Health alert over UK smog warning

People who suffer from breathing difficulties are being warned about a potentially harmful cloud of smog covering parts of the UK.

The Department for Environment, Food and Rural Affairs says the cloud is believed to be blowing in from Europe and mixing with home-grown smog to create the problem.

BBC weather forecaster, Helen Willetts, explained what has caused the smog.

  • 19 Mar 2015
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