The P4 laboratory, located in this city where the virus appeared at the end of last year, works with particularly dangerous virus strains and there are hypotheses that suggest that it was at the origin of the pandemic.

But the director of the National Biosafety Laboratory, Yuan Zhiming, denied this idea in a report on the state television station CCTV .

Without authorization, not a mosquito could enter the laboratory, Yuan said in a report that appears to have been done inside the facility, which opened in 2017.

None of our laboratory technicians could remove even a drop of water or a piece of paper, he said.

According to the director, people who imagine that we could take animals out of the laboratory to sell them or that they could escape have no idea of ​​our operation.

The theory that has more consensus is that the virus would have its origin in a bat or a pangolin and that it then passed on to man.

The likely site of contamination would be a Wuhan market where live wild animals were sold.

The epidemic has already contaminated 12 million people in the world, with more than half a million deaths.

Yuan Zhiming considered his laboratory 'natural' to be suspicious because it is the one closest to the epicenter of the epidemic.

But he says he is confident that the rumors will progressively dissipate.

There was no leakage of pathogens or human contamination" in the laboratory, built in collaboration with France, said the director.

According to Yuan, although it seems that the laboratory is "a secret black box" it is actually "very open and transparent" and hopes to host foreign researchers in the future

Despite various demands, AFP has not obtained authorization to visit the laboratory since the pandemic broke out.

The United States and Australia, among other countries, accuse China of lack of transparency and called for an international investigation into the origin of the virus.