Eleven American service members and a civilian contractor have tested positive for the new coronavirus upon their arrival in South Korea, US Forces Korea (USFK) said Monday.

Seven of the service members arrived at Osan Air Base in Pyeongtaek, south of Seoul, on US government-chartered flights, while four the others and the contractor arrived on commercial flights via Incheon International Airport, west of Seoul, according to the US military.

Eight of them tested positive on their first mandatory COVID-19 test prior to entering quarantine, while the others were confirmed to have been infected with the virus on a second test conducted before release.

All USFK-affiliated individuals arriving in South Korea are required to undergo a virus test and are quarantined for 14 days.

Medical personnel administer a second test prior to their release.

The latest cases brought the total number of USFK-related coronavirus infections to 337. (Yonhap)