SKOPJE, North Macedonia—North Macedonia’s government declared three days of mourning Thursday following a deadly overnight fire in a COVID-19 field hospital that killed 14 people and injured a dozen. The blaze broke out late Wednesday in the western city of Tetovo, where the unit had been set up following a recent spike in infections in the region that left local hospitals full. Health Minister Venko Filipce said the 14 dead ranged in age from 29 to 79. Forensics teams were working to identify them, and it was not yet clear whether all were COVID-19 patients or whether some visiting relatives might have been among them. “We will run DNA tests on the victims which will confirm whether there were members of the families,” Filipce said. “It is difficult to express in words the pain that I feel for the lost lives and the loss of their families,” he told a …