New China virus: Officials warn it 'could mutate and spread further'

A new virus that has killed nine people could mutate and spread further, Chinese health officials have warned, as they step up containment measures.

There are 440 confirmed cases, with the origin a seafood market that "conducted illegal transactions of wild animals".

It has now spread from Wuhan to several Chinese provinces as well as the US, Thailand and South Korea.

Authorities admitted that the country was now at the "most critical stage" of prevention and control.

China had earlier confirmed that human-to-human transmission of the virus had taken place.

The virus, known also as 2019-nCoV, is understood to be a new strain of coronavirus that has not previously been identified in humans.

Signs of infection include respiratory symptoms, fever, cough, shortness of breath and breathing difficulties.