Health officials are warning of a second wave of coronavirus infections after the cumulative number of infections in Seoul surpassed 1 , 000 . The latest surge originated in warehouses , churches and gyms where people often wear no face masks or come too close to each other . According to the Seoul Metropolitan Government , the cumulative number of people in the capital who tested positive for coronavirus reached 1 , 014 as of Monday , 377 of them over the past month alone and the steepest monthly increase since the first case was reported in Seoul on Jan . 24 . Small - scale group infections were reported in Gyeonggi Province surrounding Seoul and Incheon west of the capital over the past month . Some 803 cases out of the total 996 new cases reported in May came from the Seoul Metropolitan area . Jeong Eun - kyeong , the chief of the Korea Centers for Disease Control and Prevention , said , " The number of confirmed cases is suddenly surging from one a day to 15 and 20 , which shows the rapid spread of coronavirus . " All students returned to school by Monday as fifth , sixth and seventh graders became the last batch to be allowed back . Experts said proper prevention will determine the success or failure of efforts to stave off a second wave . " There seem to be many patients who are showing no symptoms , " Jeong said , " We ' re concerned about another resurgence traced to various locations in the densely populated metropolitan area . " The government has stockpiled 350 , 000 diagnostic kits in order to prepare for the threat . Meanwhile , Korea reported 38 new cases by Tuesday , 33 of them in the Seoul metropolitan area , bringing the total to 11 , 852 . [ By Bae Jun - yong ] 	 Copyright ⓒ Chosunilbo & Chosun . com