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Media captionWATCH: ‘One of two things happened’
US President Donald Trump has appeared to undercut his own intelligence agencies by suggesting he has seen evidence coronavirus originated in a Chinese laboratory.
Earlier the US national intelligence director’s office said it was still investigating how the virus began.
But the office said it had determined Covid-19 “was not manmade or genetically modified”.
China has rejected the lab theory and criticised the US response to Covid-19.
Since emerging in China last year, the virus has killed 230,000 people worldwide including 63,000 in the US.
The pandemic has seen at least 3.2 million people infected, a million of them Americans, since the virus spread from the city of Wuhan.
What did Trump say?
At the White House on Thursday, Mr Trump was asked by a reporter: “Have you seen anything at this point that gives you a high degree of confidence that the Wuhan Institute of Virology was the origin of this virus?”
“Yes, I have. Yes, I have,” said the president, without specifying. “And I think the World Health Organization [WHO] should be ashamed of themselves because they’re like the public relations agency for China.”
Asked later to clarify his comment, he said: “I can’t tell you that. I’m not allowed to tell you that.”
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He also told reporters: “Whether they [China] made a mistake, or whether it started off as a mistake and then they made another one, or did somebody do something on purpose?
“I don’t understand how traffic, how people weren’t allowed into the rest of China, but they were allowed into the rest of the world. That’s a bad, that’s a hard question for them to answer.”
The New York Times reported on Thursday that senior White House officials had asked the US intelligence community to investigate whether the virus came from a Wuhan research laboratory.
Intelligence agencies have also been tasked with determining if China and the WHO withheld information about the virus early on, unnamed officials told NBC News.
What did the intelligence service say?
In a rare public statement, the Office of the Director of National Intelligence, which oversees US spy agencies, said on Thursday it concurs with the “wide scientific consensus” regarding Covid-19’s natural origins.
“The [intelligence community] will continue to rigorously examine emerging information and intelligence to determine whether the outbreak began through contact with infected animals or if it was the result of an accident at a laboratory in Wuhan.”
It was the first clear response from American intelligence debunking conspiracy theories – both from the US and China – that the virus is a bioweapon.
What is the Wuhan lab?
The Wuhan Institute of Virology, which was founded in the 1950s, houses China’s first Biosafety Level 4 laboratory.
Such labs handle the most dangerous pathogens for which there are few available vaccines or treatments, and one of the areas the Wuhan facility studies is coronaviruses from bats.