China on Sunday expanded drastic travel restrictions to contain a viral epidemic that has killed 56 people and infected nearly 2,000, as the
United States and
France prepared to evacuate their citizens from a quarantined city at the outbreak's epicentre.
China has locked down the hard-hit province of Hubei in the country's centre in an unprecedented operation affecting tens of millions of people to slow the spread of a respiratory illness that President
Xi Jinping said posed a "grave" threat.
Originating in Hubei's capital of Wuhan, the virus has spread throughout
China and around the world -- with cases confirmed in around a dozen countries as distant as the United States.