Britain is demanding an explanation from Russia after confirming that the nerve agent that caused two people to become critically ill in southern England on Saturday is the same as that used to poison a former Russian spy earlier this year. It's thought the couple may been exposed to Novichok that was left over from an the March attack. Also scientists have warned that a rare banana species -- which could hold the key to protecting the world's edible banana crop from disease -- is in danger of extinction.
