SEOUL (REUTERS) - South Korean police arrested a foreign national for violating the country's mandated 14-day quarantine rules for the first time on Thursday (May 21), amid fears of a potential second wave of the new coronavirus.

The arrest of the 23-year-old Japanese man was the first such detention of a foreign citizen, though the country had previously arrested four South Koreans, including two from Seoul, a police station official in the capital's Seodaemun district said.

The man entered the country on May 2 with a work visa and, after a negative coronavirus test at the airport, was ordered to self-quarantine for two weeks as is mandatory for all arrivals.

Police said surveillance video footage and card transactions showed that he had broken the rules on eight out of 14 days, including for visits to restaurants, cafes and a vet.

The Japanese man, who will face a trial, was being held at the police station and would soon be sent to a detention centre, the official added.

In late March, the country's health ministry warned it would deport foreigners and South Korean citizens could face jail for violating self-quarantine rules after a surge in imported coronavirus cases.

After weeks of nearly no new domestic cases, South Korea relaxed its lockdown on May 6, but a subsequent spike in infections linked to a nightlife neighbourhood in Seoul forced a rapid rethink.

Schools reopened on Wednesday after the beginning of the Spring semester had been postponed several times since March, but the discovery of new cases in two students marred the reopening and forced 75 high schools to send pupils back home.

South Korea has reported a total 11,122 infections so far with 264 deaths.