Russia has claimed without any evidence that biological weapons are being developed in laboratories in Ukraine with support from the United States. It says material is being destroyed to conceal the country's weapons programme, but the US says this is "total nonsense" and that Russia is inventing false narratives to justify its actions in Ukraine.
Russia has accused the US and Ukraine of working with "pathogens of dangerous infections" in 30 laboratories across the country. Pathogens are microorganisms that can cause disease. Ukraine has dozens of public health laboratories that work to research and mitigate the threats of dangerous diseases. Some of these labs receive financial and other support from the US, the European Union and the World Health Organization (WHO) - as is the case in many other countries. Despite Russian claims that these are "secret" labs, details of US involvement can be found on the US embassy's website.
[Olga Robinson, Shayan Sardarizadeh and Jake Horton, BBC Reality Check and BBC Monitoring, March 15, 2022]