(ATTN: RECASTS headline, lead; UPDATES with details in paras 3, 10-11, 15-16, 19; ADDS photo)
SEOUL, Oct. 18 (Yonhap) -- South Korea's new coronavirus cases rose by double digits for a third consecutive day Sunday, but sporadic cluster infections across the country put more strain on the country's virus fight.
The country added 91 more COVID-19 cases, including 71 domestic infections, raising the total caseload to 25,199, according to the Korea Disease Control and Prevention Agency (KDCA).
The figure marked a rise from 73 daily cases Saturday and 47 on Friday as a series of sporadic mass infection cases are hampering the country's efforts to stem further spread of the virus.
New virus cases fell below the 50 mark for the first time since Sept. 29 on Friday, but a steady rise in new daily cases indicates that cases with unknown transmission routes are still lurking.
Last week, the country lowered its social distancing level to the lowest in the three-tier infection preventive measure as new daily virus cases showed a slight decrease.
Under the eased measures, operations of 10 kinds of high-risk facilities, such as karaoke rooms, gyms, buffets and large-scale cram schools with more than 300 registered students, have been allowed.
People still must follow antivirus measures such as wearing face masks and keeping entry logs.
Crowds of up to 30 percent of stadium capacity have been allowed at sports events, such as in the professional soccer and baseball leagues.
But health authorities remain alert over a possible rise in new virus cases due to growing sporadic cluster infections and increasing travelers as the country is in the height of the autumn foliage season.
They are also concerned about the eased in-person classes of students from this week.
The Ministry of Education raised the attendance cap to two-thirds for all schools last Sunday, in line with the relaxed social distancing rules nationwide.
This week, health authorities plan to conduct virus tests for 160,000 people in senior hospitals, mental hospitals and senior care facilities in greater Seoul as new virus cases rose in the facilities.
They will decide on whether to expand the tests to other facilities after assessing the situation.
Of the newly identified local infections, 18 cases were reported in Seoul, 48 cases in Gyeonggi Province and one case in the western port city of Incheon.
Cluster infections were reported at a call center in Gangnam in southern Seoul, with related cases standing at 18.
New virus cases in a rehabilitation hospital in Gwangju, Gyeonggi Province, surged to 48, two days after the first case was reported on Friday.
Other municipalities reported new infections, with the country's largest port city of Busan adding two cases and Gangwon Province reporting one more case.
The country also reported 20 new imported cases, up from 11 a day earlier, the KDCA said.
Ten cases came from Russia, with three from Nepal and one each from the Philippines, Uzbekistan, India, Kuwait, Turkey, the United States and Mexico.
The total number of people released from quarantine after making full recoveries stood at 23,312, up 54 from the previous day.
One additional death was reported, raising the death toll to 444. The fatality rate was 1.76 percent.