Rowley said authorities are "working closely with a wide range of specialists" to determine the exact nerve agent involved.
It's unlikely that radiation, harmful bacteria or a virus caused the Skripals to become unconscious, based on details reported in the media, said Dr. Lewis Nelson, chairman of emergency medicine at Rutgers New Jersey Medical School, who is not involved with the Skripals' treatment.
That said, former Russian spies have died from radiation exposure in the past. The BBC has not released the recording but published a transcript.
Ms Skripal lives in Moscow and has visited her father in the UK regularly, especially during the past two years.
Johnson also said Tuesday that there are "echoes" in this case of what happened to former Russian spy Alexander Litvinenko, who died a slow death after drinking tea laced with highly radioactive polonium-210 in a Mayfair hotel of London in 2006.
8 militaires burkinabè tués — Attaques de Ouagadougou
Elle a déclaré qu'après les premières enquêtes, parmi la soixantaine de personnes interrogées, huit (08) ont été mis aux arrêts. Des sources sécuritaires ont cependant indiqué qu'ils portaient des treillis militaires.
Therapist Marina Travkova said the fact that three journalists, all in their late 20s or early 30s, have come forward about being sexually harassed shows that younger, well-travelled Russians who grew up after the fall of the Soviet Union view male behavior differently from an older generation.
The area in and around Salisbury has been cordoned off.
Commenting on the situation, Russian Foreign Ministry spokeswoman Maria Zakharova emphasized that the suspected contamination incident is being used as fuel for the anti-Russia campaign. Moreover, symptoms from radiation poisoning take days to weeks to occur, and it appears that the symptoms developed quickly in the Skripals' case, Nelson said.
The Skripal case has come shortly before Russia's presidential election on March 18, which Putin is expected to win comfortably, extending his rule by a further six years.
Russia last year passed a bill to decriminalize some forms of domestic violence, and in 2015 Russian Orthodox activists launched a petition, supported by the Church, to ban abortions.
Britain blamed Russia for the 2006 poisoning of former Russian spy and Kremlin critic Alexander Litvinenko.
British Prime Minister Theresa May has backed moves to snub the World Cup in Russia - if Kremlin links are proven in the Salisbury contamination scare.
Trump suggests US may someday have 'president for life'
Chinese Navy also expanded its global reach with flotilla ships sailing through the far-off oceans to expand China's influence. Analysts view these steps as equally significant as the removal of term limits in their impact on Chinese politics.
While the network's main role is to prevent and investigate terrorist activity, it can also be assigned to other specialist probes including inquiries relating to war crimes, counter-espionage and the Official Secrets Act.
Politicians, analysts and MPs say Vladimir Putin "could be responsible". A spokesperson said it is not yet clear whether the incident is related to the suspected poisoning of Skripal and Yulia.
Britain's Foreign Secretary Boris Johnson warned on Tuesday the government would respond "robustly" if the poisoning turned out to be the work of a foreign state. The UK cannot and will not tolerate state-sponsored terrorism of any kind'.
"Readers are presented with various theories, which boil down to ways of demonising Russia".
A spokesman for the Russian embassy told Russian news agency TASS that the case was turning into an "anti-Russia crusade".
The desperation of the people especially those in the military and in oil industry, I see as forcing action and one crisis after another.
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