A mysterious SARS-like virus has killed a third person and spread around China – including to Beijing – authorities said Monday, fuelling fears of a major outbreak as millions begin traveling for the Lunar New Year in humanity’s biggest migration.

The new coronavirus strain, first discovered in the central city of Wuhan, has caused alarm because of its connection to Severe Acute Respiratory Syndrome (SARS), which killed nearly 650 people across mainland China and Hong Kong in 2002-2003.