Almost 250 million people in China may have caught Covid-19 in the first 20 days of December, according to an internal estimate from the nation’s top health officials, Bloomberg News and the Financial Times reported Friday.

If correct, the estimate – which CNN cannot independently confirm – would account for roughly 18% of China’s 1.4 billion people and represent the largest Covid-19 outbreak to date globally.

The figures cited were presented during an internal meeting of China’s National Health Commission (NHC) on Wednesday, according to both outlets – which cited sources familiar with the matter or involved in the discussions. The NHC summary of Wednesday’s meeting said it delved into the treatment of patients affected by the new outbreak.

On Friday, a copy of what was purportedly the NHC meeting notes was circulated on Chinese social media and seen by CNN; the authenticity of the document has not been verified and the NHC did not immediately respond to a request for comment.