Spy poison deadline passes as Russia threatens 'response'

The Russian chemist who first revealed the existence of novichok nerve agents says only the Russians can be behind the weapon's use in Britain against a former spy and his daughter.
Dr Vil Mirzayanov, 83, came to the United States in 1995 after 30 years of working for the State Scientific Research Institute of Organic Chemistry and Technology, or GNIIOKhT.
It was he who in the early 1990s revealed the existence of that class of ultra-powerful nerve agents.
He did so first in the Russian media as it opened up with the collapse of the Soviet Union, and later, with chemical formulas at hand, in his book "State Secrets," published in 2007.
Dr Mirzayanov has told Sky News people exposed to even tiny traces of the nerve agent used to attack Sergei Skripal and his daughter in Salisbury could be in danger of developing symptoms in years to come.
He helped make "novichok", the class of nerve agents the British government says was used in the Salisbury attack.
But responding to an inquiry from Sky News, Dr Jenny Harries, Deputy Medical Director at Public Health England, said: "PHE has been working very closely with the police and national experts on chemical weapons since the start of the incident and our risk assessment is based on knowledge of the chemical used.
"Our advice remains that the risk to the general public is low."
What options are available to Theresa May?
Sky Correspondent Rebecca Williams is in Salisbury live this morning on Sunrise to discuss the latest developments in the investigation and British response to Russia...