A laboratory leak in China is now considered the most likely origin for the COVID pandemic, according to a classified US Energy Department report obtained by the Wall Street Journal on Sunday.
This puts the Energy Department's views in line with that of the FBI, which concluded that an accident at a Chinese lab resulted in the spread of COVID-19.
However, while Energy Department's new conclusion was made with new intelligence, it is still made with "low confidence" and a spokesperson declined to discuss any details of its investigation, according to the Wall Street Journal.
US intelligence agencies remain split on the origin of the COVID pandemic
The Energy Department's report underscores how split conclusions are in the US on the origin of the COVID-19 pandemic.
Some, like the CIA, remain undecided. Others, like the National Intelligence Council, say that the virus was spread by an infected animal, which caused it to jump over to humans through zoonotic transmission, the Wall Street Journal reported.
Previously, many in the US pushed back against claims that the virus, first spotted in Wuhan, China, originated in a leak at a local virology lab. However, more intelligence reports claim it may have been possible.
In particular, an assessment by the US State Department in 2018 as well as internal Chinese reports state that biosafety measures at the lab were a subject of some concern.
A US intelligence report circulated during former president Donald Trump's administration alleged that three researchers at China's Wuhan Institute of Virology became so ill in November 2019 that they sought hospital care, US government sources said.
US officials have accused China of a lack of transparency on the virus' origin, a charge Beijing has denied.
China continues to deny any claims that the virus originated in a lab leak, and has also suggested it originated outside the country.
Reuters contributed to this report.