South Korea's new COVID-19 cases spiked to over 350,000 on Tuesday, adding to concerns that infections could spike again as the accumulated caseload nears 10 million.

The country reported 353,980 new COVID-19 infections as of midnight, raising the total caseload to 9,936,540, the Korea Disease Control and Prevention Agency (KDCA) said.

The total caseload is expected to breach the grim milestone of the 10 million mark within the day, meaning 1 out of 5 South Koreans have become infected with COVID-19.

Tuesday's tally marked a sharp climb from 209,169 reported Monday. The number of new daily cases usually shrinks at the beginning of the week due to less testing over the weekend.

The death toll from COVID-19 came to 13,141, up 384 from Monday, the KDCA said. Tuesday's death toll is the second highest following the 429 logged Thursday.

The fatality rate was 0.13 percent.

The number of critically ill patients stood at 1,104, down 26 from the previous day. The daily tally has remained over 1,000 for nearly two weeks.

Concerns lingered that daily infections could spike again as the government eased social distancing rules Monday as part of efforts to help small merchants and business owners taking the brunt of the pandemic due to less foot traffic and consumption.

Despite an earlier estimate that the current pandemic could peak Wednesday, health authorities cited the possibility of the current outbreak continuing due to the fast spread of the so-called stealth omicron, which has a 30 percent higher transmission rate than the original omicron.

Despite lingering concerns, the government on Monday eased the limit on private gatherings to eight people from the previous six while maintaining the 11 p.m. business curfew.

Also, fully vaccinated international arrivals are required to submit their health status, such as PCR tests, and do not have to go through the mandatory quarantine.

Authorities earlier estimated that key indicators, such as the fatality rate or the rate of patients in critical condition, would peak within the next two to three weeks.

The hospital bed occupancy rate for seriously ill COVID-19 patients came to 67.3 percent Tuesday, still remaining manageable within the country's medical response capacity.

The number of people receiving at-home treatment stood at 1,821,962 on Tuesday, down 172,024 from a day earlier, the KDCA said.

Of the domestic cases, Seoul reported 65,033 new infections, with the surrounding Gyeonggi Province logging 96,256. The western port city of Incheon reported 17,568.

As of midnight Monday, 32.42 million people out of the 52 million population, or 63.2 percent, had received booster shots. Fully vaccinated people came to 44.46 million, representing 86.6 percent, the KDCA said. (Yonhap)