South Korea's daily new virus cases remained under 600 for the second straight day Saturday, as health authorities have decided to extend the current social distancing rules for another three weeks to stem cluster infections.

The country reported 565 more COVID-19 cases, including 525 local infections, raising the total caseload to 147,422, the Korea Disease Control and Prevention Agency said.

The daily tally marked an increase of nine from Friday's 556 cases but stayed in the mid-500s for the second consecutive day.

Daily virus cases stayed in the 400s on Monday and Tuesday but spiked to the 600 range on Wednesday and Thursday.

Daily caseloads here have been going through some ups and downs between the 400s and 700s in recent months with no significant signs of a letup due to sporadic cluster infections nationwide.

Health authorities said the current distancing rules will be extended until July 4. Currently, the greater Seoul area, Daegu, Jeju Island and a few other areas are under the Level 2 distancing, the third highest in the country's five-tier COVID-19 alert system, while many other regions are under Level 1.5 amid the ban of private gatherings of five or more people.

Under the new scheme, the authorities plan to ease business curfews, with restaurants and entertainment facilities in the capital area permitted to operate until midnight, an extension from the current limit of 10 p.m.

The partly eased virus curbs came as the country's inoculation drive is gaining traction.

A total of 11.39 million people have received their first shots of COVID-19 vaccines, including 792,835 the previous day, accounting for 22.2 percent of the country's population, since the country started its vaccination program on Feb. 26. 

The KDCA said 2.8 million people, or 5.6 percent of the population, have been fully vaccinated.

South Korea is trying to inoculate 14 million people by the end of this month and 36 million by September in a move to achieve herd immunity in November, but it hopes it can reach the goal earlier than expected with the increased vaccine rollout.

In addition to vaccines from AstraZeneca and Pfizer, the country started to use the Janssen vaccine supplied by the US government for reserve forces, civil defense members and others in charge of defense and foreign affairs from Thursday.

A total of 453,732 people received Janssen's single-dose COVID-19 vaccine in the first two days of its inoculation.

Health authorities said the vaccine from Moderna is expected to be available for inoculation next week.

Of the 541 newly locally transmitted cases, 205 came from Seoul, 170 from Gyeonggi Province and 19 from Incheon, 40 kilometers west of the capital.

The southeastern port city of Busan, the country's second-largest city, reported 13 more cases.

There were 40 additional imported cases, raising the total to 9,292.

Of the newly confirmed cases from overseas, 34 were from Asian nations, excluding China, and three were from Africa.

The KDCA data showed the number of seriously or critically ill COVID-19 patients was 155, up two from the previous day.

The total number of people released from quarantine after making full recoveries was 138,037, up 813 from a day earlier, with 7,403 people being isolated for COVID-19 treatment. (Yonhap)