There’s a mysterious virus in China and it is spreading.

The BBC reports that Chinese authorities have confirmed the spread of the mysterious virus outside of Wuhan city and there have been 139 new cases.

Besides Japan and Thailand, South Korea has also reported its first confirmed case of the virus. It has also been established by health officials that this infection which first appeared in Wuhan is a strain of coronavirus.

Three have died from the respiratory illness.

The health officials also state that this has led to an outbreak of viral pneumonia but further details are hard to come by.

A third person has died of the virus in Wuhan over the weekend. As of Sunday evening, 170 people from Wuhan were being treated for the virus while nine were in a critical condition. China’s National Health Commission on Sunday said the virus was “still preventable and controllable” but it also mentioned that close monitoring was needed given that a lot remains unknown about this virus.

The BBC further reports that the virus appears to have crossed the species barrier and come from infected animals at a seafood and wildlife market in Wuhan.

“As more… cases are identified and more analysis undertaken, we will get a clearer picture of disease severity and transmission patterns,” WHO wrote on Twitter.