China is redoubling efforts to control new virus outbreaks with a lockdown of the 13 million residents of the northern city of Xi’an following a spike in coronavirus cases. The measure comes just weeks before the country hosts the Winter Olympics in Beijing, roughly 1,000 kilometers (6210 miles) to the west. There was no word on whether the virus was the newly surging omicron variant or the far more common delta. China has recorded just seven omicron cases — four in the southern manufacturing […]