South Korea's daily Covid-19 cases on Wednesday topped the 2-thousand mark again.
This came after the nation's daily infections had stayed under 2-thousand since last Wednesday.
All but 33 cases were locally transmitted raising the total number of cases to over 253-thousand.
For two days in a row, more than 70-percent of cases were from the Greater Seoul area.
"Looking at the time frame, people travelled from the capital region to outside the capital during the past holiday and it appears that they are coming back to the capital region again right now.
So-called breakthrough infections are also surging in Korea now reaching over 3-thousand cases in total.
Authorities said these rates were higher for people in their 30s than for older people.
The authorities reported, so far, those given with Johnson and Johnson's Janssen vaccine have the most breakthrough infections.
However, no breakthrough cases have been reported from people vaccinated with the Moderna shot.
Meanwhile, the Delta variant is now responsible for around 95 percent of new infections in the country.
Considering the rapid surge from having only 3-percent two months ago, the authorities said the fourth wave of infections is likely to be around for the foreseeable future.
And, to prevent the spread of the Delta variant particularly during the Chuseok holiday this Friday, the authorities are set to announce special prevention guidelines for the holiday as well as social distancing measures for next week.
Choi Won-jong, Arirang News.