South Korea has reported another day of more than 500 new cases of COVID-19 along with one more virus-related fatality.

The Korea Disease Control and Prevention Agency said Thursday 540 local infections and 17 imported cases were confirmed in the last 24 hours, pushing the country's caseload to 149,731.

The death toll rose to 1,994.

More than half of latest cases came from the greater Seoul area.

But cluster infections continue to pop up across the country from public facilities, workplaces, schools and group gatherings.

Health authorities decided earlier this week to maintain current social distancing and quarantine rules until July 4, after which a revamped four-tier distancing scheme will be rolled out, in line with the changing situation in the country.

With the national vaccination campaign picking up speed, government officials said they expect inoculations to surpass 14 million by the end of day.

The KDCA said among those who have received shots, more than 3.7 million, or over 7 percent of the population, have so far been fully vaccinated against the coronavirus.

Authorities are set to announce the vaccination plan for the third quarter, which will expand eligibility to people aged 18 to 59.