South Korea sees 248 new cases as coronavirus spikes

South Korea has counted its 18th straight day of triple-digit daily jumps in coronavirus cases as its health minister warned about an increase in transmissions gone untraced, and infections among senior citizens.

The 248 new cases reported by the Korea Centres for Disease Control and Prevention Monday brought the national caseload to 19,947, including 324 deaths.

KCDC said 187 of the new cases came from the densely populated Seoul metropolitan area, which have been at the centre of the viral resurgence this month.

But infections were also reported in major cities across the country, including Busan, Daejeon, Ulsan and Daegu, which was the epicentre of the country's previous major outbreak in late February and March that was stabilised by April.

Health Minister Park Neung-hoo during a virus meeting said it has become difficult for epidemiological workers to track transmissions and predict infection routes, saying they haven't been able to trace the infection source of more than 20% of the cases found in the past two weeks.

Officials are also concerned that the death toll could rise because many of those who tested positive this month were 60 years or older, an age group that's more likely to experience serious health complications caused by the virus.