South Korea has detected its first COVID-19 cases suspected to be the new strain, omicron. 

The Ministry of Health and Welfare and the Korea Disease Control and Prevention Agency(KDCA) said on Tuesday that a couple who recently returned from a trip to Nigeria underwent tests to see whether they are omicron cases. The test result will likely come out on Wednesday night. 

The couple, who are both in their 40s and visited the African country between November 14 and Tuesday of last week after completing Moderna vaccination on October 28, were diagnosed with COVID-19 last Thursday, a day after arriving in Incheon, where they reside. 

Health authorities discovered that one of their acquaintances and a family member were also infected with the virus following their contacts with the couple, raising the number of the suspect cases of the omicron variant to four. 

The government said it is also tracking over 40 other people who arrived on the same flight as the couple. 

Testing is also underway on two foreign nationals who tested positive for COVID-19 in Ulsan on Tuesday. They recently arrived from the Netherlands and Germany, two of the countries reporting omicron cases.