High levels of air pollution across many parts of Britain are continuing to weigh heavily over the country.
Data from Britain's environment agency called Defra, says pollution levels over London remain at a warning level of 10. Now, health warnings have been stepped up for people with lung, heart and respiratory conditions. Forecasters say the unusually high levels are because of sand dust from the Sahara region, coupled with the local air pollution. However, they expect the smog to drop by Saturday. The pollution comes as the European Union has launched legal proceedings against the UK for failing to reduce excessive levels of nitrogen dioxide in the air.