NEW YORK - The United States secretly manufactured biological weapons in Ukraine. It trained birds to carry viruses into Russia. It created Covid-19. It operated laboratories in Nigeria that engineered this year's outbreak of monkeypox.
Of the many falsehoods that the Kremlin has spread since the war in Ukraine began more than six months ago, some of the most outlandish and yet enduring have been those accusing the US of operating clandestine biological research programmes to wreak havoc around the globe.
The US and others have dismissed the accusations as preposterous, and Russia has offered no proof.
Yet the claims continue to circulate. Backed at times by China's diplomats and state media, they have ebbed and flowed in international news reports, fuelling conspiracy theories that linger online.
In Geneva this week, Russia has commanded an international forum to air its unsupported assertions again.
The Biological Weapons Convention, the international treaty that since 1975 has barred the development and use of weapons made of biological toxins or viruses, gives member nations the authority to request a formal hearing of violations, and Russia has invoked the first one in a quarter-century.
"This is the military biological Pandora's box, which the United States has opened and filled more than once," Ms Irina Yarovaya, the deputy chair of the Russia's Lower House of Parliament, the State Duma, said last month.
She is leading a parliamentary committee that was formed to "investigate" American support for biological research laboratories in Ukraine and elsewhere.
Virtually no Western officials or experts expect Russia to produce, during the weeklong gathering, facts that corroborate the accusations.
If the past is any guide, that will not stop Russia from making them. Experts say Russia is likely to use the mere existence of the investigative session, much of which will take place behind closed doors, to give its claims a patina of legitimacy.
Russia's propaganda campaign has sought to justify the invasion ordered by President Vladimir Putin, who in April cited a "network of Western bioweapons labs" as one of the threats that forced Russia to act.
More broadly, though, the flurry of accusations has sought to discredit the US and its allies - Ukraine's most powerful supporters and, increasingly, the source of arms being used to fight Russian forces.
Even when unsupported by fact, the accusations have played into preexisting attitudes toward American dominance in foreign affairs. The consequence has been to sow division and doubt - not necessarily to build support for Russia's invasion but to deflect some of the blame to the US and the North Atlantic Treaty Organisation (Nato).
The notoriety of Russia's accusations about secret weapons production could also erode confidence in genuine biological research, much as the debate over the origins of Covid-19 has.
"The message is constantly about these labs, and that will erode confidence in that infrastructure and the work that's being performed," said Dr Filippa Lentzos, an expert on biological threats and security at King's College London.
"And it will significantly undermine global biosafety and biosecurity efforts, so it does have consequences."
Russia added the outbreak of monkeypox to its list of American transgressions in April.
General Igor Kirillov, the head of the Russian army's radiological, chemical and biological defence force, insinuated that the US had started the latest outbreak because it supported four research laboratories in Nigeria where the epidemic began to spread.
In the months after the general's comments, there were nearly 4,000 articles in Russian media, many of them shared on Twitter, Facebook and other social media platforms, according to research conducted by Zignal Labs for The New York Times.
For evidence of a conspiracy, some of the Russian reports pointed to a simulation in 2021 at the Munich Security Conference, an annual gathering of defence officials and experts from around the world.
The simulation, intended to test how well countries would contain a new pandemic, posited a hypothetical monkeypox outbreak that began in a fictional country called Brinia and caused 270 million deaths.
Russia's accusations have appeared in news reports in many countries, especially in Africa and the Middle East, regions that have become diplomatic battlegrounds between the United States, Russia and China.
The state media in China routinely amplifies Russian claims about the war with Ukraine and about secret biological weapons research, as part of its own information battle with the US that began with the debate over the spread of Covid-19.
China's heavily censored Internet, has also freely circulated conspiracy theories about a possible U.S. role in the spread of monkeypox, as Bloomberg reported.
Russia's efforts to push the claims about biological weapons come from an old Russia propaganda playbook, adapted to the age of social media.
Researchers at the RAND Corporation called the Russian strategy a "fire hose of falsehood," inundating the public with huge numbers of claims that are designed to deflect attention and cause confusion and distrust as much as to provide an alternative point of view.
On Monday, Russia will make a presentation before representatives of the 184 nations that have signed the Biological Weapons Convention. The United States, Ukraine and other countries will be able to respond later in the week.
Because the treaty has no verification or enforcement provisions, there will be no official ruling on Russia's claims, but on Friday, nations can state their positions.
Dr Lentzos of King's College London said that because of the format - and geopolitics - many countries might be unwilling to publicly contradict Russia or its biggest backer, China.
"There's a big silent majority that just wants to sit on the fence," Dr Lentzos said.
"They don't really want to take a side because it could hurt their interests either way. And so the big question is not 'do these guys believe it or not?' It's to what extent are they motivated to act on it and speak out." NYTIMES