St Petersburg plunged into darkness
St Petersburg marked earth hour by turning out the lights of Palace Square. Climate change protesters held a candle lit vigil at 8.30pm local time.
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Heatwave advice issued during coldest spring since 1979
Public Health England publishes its guide on coping with the dangers of severe hot weather - as spring is set to be the coldest since 1979
Why this spring is set to be the coldest since 1979
Friday's weather really will be atrocious for England and Wales. But Saturday and Sunday may be the last chance for a BBQ for a while.
The global war on terror is dead
Obama last night decided America's longest-ever conflict had to be re-defined. So the White House offered the world's bad guys a new deal.