K-pop megastars BTS cancelled Friday four Seoul concerts due in April as South Korea's novel coronavirus cases jumped by nearly 600 -- a larger rise than the daily increase reported in China, where the disease first emerged. The seven-piece boyband -- currently one of the biggest acts in the world -- had scheduled four gigs at the capital's Olympic Stadium to promote their new album "Map of the Soul: 7". More than 200,000 fans were expected to attend, their agency Big Hit Entertainment said in a statement, with "a number of global production companies and a large group of expert international crew" also involved. It was "impossible at this time to predict the scale of the outbreak", it said, creating so much uncertainty it was "unavoidable" the shows were cancelled "without further delay". "We must take into consideration the health and safety of hundreds of thousands of guests as well as our artists," it added. The BTS concerts are the latest events to be cancelled or postponed as the outbreak has spread in the world's 12th-largest economy, including the K-league football season and the World Team Table Tennis Championships. The new school term has been delayed by one week and the US and South Korean militaries have postponed forthcoming joint exercises. Hyundai Motor also suspended operations at one of its Ulsan plants after an employee tested positive for the coronavirus. The auto manufacturer had temporarily stopped all domestic production earlier this month because of a lack of parts due to the outbreak in China. - More infections - South Korea reported 571 new cases on Friday, taking its total -- the highest in the world outside China -- to 2,337, the Korea Centers for Disease Control and Prevention (KCDC) said. That was a larger increase than the 327 reported by China, where nearly 2,800 people have died. The World Health Organization has warned that all countries should ensure their health systems were prepared for an outbreak. The epidemic was at a "decisive point" globally, its chief Tedros Adhanom Ghebreyesus said Thursday and countries could still contain the epidemic if they "act aggressively now". The South has an advanced health system and a free media, factors observers say improve the reliability of its statistics, and its numbers are expected to rise further as it carries out checks on more than 260,000 people associated with the Shincheonji Church of Jesus. The secretive entity is linked to around half of the nation's cases. A 61-year-old female member developed a fever on February 10, but attended at least four church services in Daegu -- the country's fourth-largest city with a population of 2.5 million -- before being diagnosed. More than 85 percent of South Korea's coronavirus cases are in Daegu and the neighbouring province of North Gyeongsang, according to the KCDC. The country's death toll remains at 13. - Bulletproof Boy Scouts - One BTS fan said on the band's Facebook page that the decision on the concerts was a "regrettable but inevitable call", although others lamented that the shows had been cancelled, rather than postponed. BTS -- or Bangtan Sonyeondan, which translates as Bulletproof Boy Scouts -- are the first K-pop group to top charts in the US and Britain. Their latest effort was given a simultaneous worldwide release online last Friday, becoming the most pre-ordered South Korean album of all time, with more than four million copies sold before its release. The coronavirus outbreak already forced them to livestream a press conference earlier this week, the seven members waving and bowing to a virtually empty hall, and urging fans to take care of themselves. On Friday they appeared on KBS television's Music Bank show, which dispensed with its usual studio audience. "Many people are concerned about coronavirus," said member Jin. "I hope we overcome this challenge."