On Tuesday, the number of daily coronavirus cases in South Korea fell below 4,000 for the third consecutive day as a result of stricter social distancing rules, but health officials remain on high alert after the first omicron-related deaths were reported a day earlier.

Approximately 3,024 new COVID-19 infections were reported in the country, including 2,889 local infections, bringing the total number of cases to 645,226 cases, according to the Korea Disease Control and Prevention Agency (KDCA).

The figure was down 105 from the previous day and down 841 from the same day the previous week, according to the Bureau of Labor Statistics. The number of reported cases fell below the 4,000 mark for the third consecutive day, with 3,832 cases reported Sunday and 3,126 cases reported Monday, marking the lowest daily total in three weeks.

South Korea reported 51 additional COVID-19 deaths, bringing the total number of deaths to 5,781, according to the KDCA. The number of deaths was lower than the previous day's total of 36. The fatality rate was 0.9 percent at the time of the survey.

The total number of critically ill COVID-19 patients was 973, a decrease of 42 from the previous day. For the first time in 15 days, the number of critical cases fell below 1,000. As long as the government maintains strict anti-virus restrictions, the number of daily cases is expected to decrease.

Early in November, the government relaxed long-enforced pandemic-era restrictions as part of efforts to gradually return to normalcy under the "living with COVID-19" scheme, which calls for a phased return to normalcy.

As a result, on December 15, the number of daily cases reached a record high of 7,848. The government responded by reimposing antivirus regulations, which were supposed to be in effect for two weeks but were extended until Sunday.

The government has extended the enforcement of those rules for an additional two weeks, until January 16. The rules include a four-person limit on private gatherings across the country and a 9 p.m. business hour curfew on cafes and restaurants, among other restrictions.

Despite the fact that the country has reported its first omicron-linked death cases, health officials remain on high alert.

Coronavirus patients in their 90s were reported to have died in Gwangju, 330 kilometers south of Seoul, with one of them posthumously confirmed to have been infected with omicron and the other suspected to have been infected with the potentially more transmissible COVID-19 variant, according to the report.

There have been no reported cases of omicron-linked deaths in South Korea since the variant was first reported in the country on December 1.

Meanwhile, Seoul reported 903 cases out of the 2,993 cases of locally transmitted COVID-19, while 916 cases came from the neighboring Gyeonggi Province and 162 cases came from Incheon, a port city west of the capital.

The number of cases from other countries reached 135, bringing the total number of cases to 17,866.

According to the Korea Department of Health and Welfare, a total of 42.6 million people, or 83.1 percent of the country's 52 million population, have been fully vaccinated, and approximately 19 million people, or 37 percent, have received booster shots.