South Korea reported another record spike in the number of new coronavirus cases on Monday, with most new cases centered in the southwestern city of Daegu, where health authorities are shifting the focus of the anti-virus fight to containing its further spread.

The 161 additional cases of the new coronavirus brought the total number of infections in South Korea to 763. Also, a 62-year-old man, who is tied to a hospital in Cheongdo, near Daegu, died of the virus on Sunday, bringing the nation's death toll to 7.

Daegu, where 2.5 million people have been asked to stay indoors, saw its confirmed cases jump by 155 to 442 on Monday morning, despite efforts to stem the spread of the virus, the Korea Centers for Disease Control and Prevention (KCDC) said in a statement.

Two clusters of infections -- at a branch of a religious sect in Daegu and a hospital in the neighboring county of Cheongdo -- have continued to expand sharply, taking up about three-quarters of the total cases in the country. About 60 percent of the total cases are linked to church services at the Daegu-based Shincheonji church and 15 percent to Daenam Hospital in Cheongdo.

Although health authorities voiced hope that the virus can be contained, experts said the virus may have spread more widely nationwide as cases with no clear links to China or confirmed cases continued to be discovered in Seoul and other regions.

Vice Health and Welfare Minister Kim Gang-lip told reporters, "If authorities fail to contain the spread of the COVID-19 in Daegu, there is a high possibility that COVID-19 could spread nationwide."

To beef up the first line of defense, authorities will swiftly find patients with mild symptoms and isolate them, Kim said.

Health authorities will check about 28,000 people in Daegu who show flu symptoms over the past two weeks, officials said.

"This is a stage where nationwide spread is very worrisome when local transmission (in Daegu) expands," Kim told reporters.

With health authorities preemptively isolating potential patients with mild symptoms, Kim said authorities will try to "stabilize the situation within four weeks."

Despite an alarming surge in confirmed cases in recent days, the government has no plan to expand entry bans on foreign nationals from China's other provinces, officials said.

Currently, South Korea bans foreign nationals entering the country from China's Hubei province, the epicenter of the virus outbreak.

A petition calling for President Moon Jae-in to expand entry bans to China's other provinces has exceeded 700,000.

KCDC Director Jung Eun-Kyeong told reporters that two more virus patients are in critical condition and another 14 patients have been receiving oxygen treatment.

The virus has infected a 16-month-old baby and a four-year-old child, but they are in stable condition, Jung said.

The government revised its public health guidance, ordering people with fever or respiratory symptoms to stop going to schools and companies and refrain from going outside, Jung said.

On Sunday, South Korea raised its virus alert to the highest, or "red," level -- the first time it has done so since the 2009 outbreak of H1N1 swine flu.

The top alert level allows authorities to order the temporary shutdown of schools and cut flights to and from South Korea.

The education ministry has instructed all kindergartens and schools to delay their new semester by a week in an effort to prevent the virus from spreading more widely.

So far, seven people have died in South Korea from the new virus since its first outbreak in late January.

The KCDC did not elaborate on whether the seventh victim, the 286th infected patient, had an underlying illness. Of the seven deaths, five have been linked to the Cheongdo hospital.

Of the 161 new cases, 142 are in Daegu, 300 kilometers southeast of Seoul, and neighboring North Gyeongsang Province.

Another three were reported in Seoul, the KCDC said in a statement.

Authorities said they have acquired a list of members from the Daegu-based Shincheonji church and are closely monitoring them.

The KCDC earlier said it has placed more than 9,334 Shincheonji members in self-quarantine. Of them, 1,248 have shown COVID-19-related symptoms.

On Monday, Busan and Gwangju reported two more cases and one more case, respectively. Seoul's neighboring Gyeonggi Province reported 10 more cases, the KCDC said.

South Korea confirmed its first new coronavirus case from a Chinese woman from Wuhan, the epicenter of the virus outbreak, on Jan. 20. 

South Korea will release four more novel coronavirus patients Monday after they were declared virus-free, bringing the total number of fully recovered patients here to 22, the KCDC said.

The number of people being checked for the virus and under quarantine came to 8,725, it added. The country has tested a total of 27,852 suspected cases, with 19,127 testing negative. (Yonhap)