A BBC investigation has found that Russian media and officials presented false claims about a US-funded laboratory in neighbouring Georgia.
The Russian Foreign Ministry, Defence Ministry and pro-Kremlin media claimed recently that untested drugs were given to Georgian citizens at the lab, resulting in a large number of deaths.
The US has accused Russia of disinformation in order to distract attention away from incidents such as the Salisbury poisonings.
Correspondent: Steve Rosenberg
Producer: Will Vernon
Camera/editor: Matt Goddard
This story is part of a series by the BBC on disinformation and fake news – a global problem challenging the way we share information and perceive the world around us.
To see more stories and learn more about the series visit www.bbc.co.uk/fakenews