British Prime Minister Theresa May threatens retaliation against Russia over ex-spy poisoning 01:56. LONDON-- The use of Russian-developed chemical nerve agent Novichok to poison ex-spy Sergei ...

Nerve agents were created by accident in the 1930s by scientists looking to create a better pesticide. Governments — both in the U.S. and abroad — started experimenting with the chemicals in ...

Nerve agent used in ex-Russian spy attack . British police reveal nerve agent used to poison former Russian spy 02:35. SALISBURY, England-- British police have revealed the substance used to ...

Experts are increasingly confident that a powerful nerve agent was used to kill and injure victims in an attack on a rebel-held region of Syria on Tuesday. More than 70 people were killed in a ...

The March 4 nerve agent poisoning of a former Russian double agent in Britain has chilled relations between Moscow and the West.Here is what we know about ...

Nerve agents like Novichok and sarin are the most toxic poisons in the world. Novichok , which appears to have been used to poison Russian spy Sergei Skripal and his daughter is one of the ...

The use of a nerve agent would suggest Syria did not get rid of its military stockpiles as it agreed to do after a 2013 nerve agent attack killed more than 1,000 Syrians.

The investigation into the nerve agent attack on a former Russian spy in the UK has broadened as police revealed that 21 people had received medical attention in the aftermath of the incident.

The class of nerve agent that British authorities believe was used to poison Sergei Skripal and his daughter in the English city of Salisbury is among the deadliest chemical weapons ever devised.

Nerve agents like novichok, sarin and VX can produce symptoms similar to a heavy cold at first, but they kill in minutes and spread fear almost as toxic as the substances themselves.