One US service member based in South Korea and four individuals affiliated with the US Forces Korea (USFK) have tested positive for the new coronavirus, the US military said Friday.

The service member stationed in Camp Humphreys in Pyeongtaek, some 70 kilometers south of Seoul, tested positive Wednesday after undergoing a virus test as part of the command's enhanced surveillance scheme, according to the USFK.

One civilian worker based in its Yongsan garrison in central Seoul and two family members of a US service member were confirmed to have been infected Tuesday during their mandatory test required to exit quarantine for COVID-19.

The fifth one is a family member of a US government employee who tested positive on Jan. 17 following direct contact with another family member who was previously diagnosed with the virus, USFK said, adding it was informed of the case Wednesday without specifying reasons.

"USFK health professionals determined contact tracing was limited due to these individuals being in quarantine," USFK said in a statement.

The latest cases raised the total number of infections reported among the USFK-affiliated population to 682, most of whom tested positive upon their arrival here from the US. (Yonhap)