China has been ordered to stay indoors over new coronavirus fears.All 13 million residents in the northern city of Xi’an were plunged into a strict lockdown on Wednesday, with only one person per household allowed to leave for necessities every two days.The city's authorities outlined the rules on its official Weibo social media account and specified only in the event of an emergency should they be broken.Fleeing from Xi’an has also been outlawed as the city faces not only a new wave of Covid-19 but a mystery hemorrhagic fever too.Everyone in the city is being tested for both illnesses.In its statement, the government said residents "should not leave the city unless necessary" and anyone who tries must apply with evidence of "special.