FBI Director Christopher Wray has said that the bureau believes Covid-19 “most likely” originated in a “Chinese government-controlled lab”.
“The FBI has for quite some time now assessed that the origins of the pandemic are most likely a potential lab incident,” he told Fox News.
It is the first public confirmation of the FBI’s classified judgement of how the pandemic virus emerged.
In response, Beijing accused Washington of “political manipulation”.
Other US government agencies have drawn differing conclusions to the FBI’s, with varying degrees of confidence in their findings.
Some of them have said – but with a low level of certainty – that the virus did not start in a lab but instead jumped from animals to humans.
The White House has said there is no consensus across the US government on the origins.
A joint China-World Health Organization (WHO) investigation in 2021 called the lab leak theory “extremely unlikely”.
However, the WHO investigation was deeply criticised and its director-general has since called for a new inquiry, saying: “All hypotheses remain open and require further study.”
Mr Wray’s comments come a day after the US ambassador to China called for the country to “be more honest” about Covid’s origins.
In his interview on Tuesday, Mr Wray said China “has been doing its best to try to thwart and obfuscate” efforts to identify the source of the global pandemic.
“And that’s unfortunate for everybody,” he said.
Following his comments, Chinese foreign ministry spokeswoman Mao Ning said: “The conclusions they have reached have no credibility to speak of.”
Some studies suggest the virus made the leap from animals to humans in Wuhan, China, possibly at the city’s seafood and wildlife market.
The market is a 40-minute drive from a world-leading virus laboratory, the Wuhan Institute of Virology, which conducted research into coronaviruses.