Korea's health authorities said Tuesday the outbreak of norovirus infections in the Olympic host town of PyeongChang was likely caused by contaminated water from a lodging facility where private security staff for the Winter Games stayed.

The cooking water at the facility in PyeongChang, some 180 kilometers east of Seoul, was possibly contaminated, the Korea Centers for Disease Control and Prevention said in its interim report.

The health authorities launched an epidemiological probe last week after dozens of security workers for the PyeongChang Winter Olympics tested positive for the virus following symptoms of stomach pain and diarrhea.

Among 1,014 people who used the facility, 94 were confirmed to have been affected by the virus, the KCDC said, adding that new cases were rarely reported once the accommodation stopped serving meals.

Those who had food from the center were 6.5 times more likely to be infected with the virus than those who did not eat meals there, it said.

A total of 194 cases of norovirus infections had been confirmed as of Monday since the first outbreak in the Olympic host town last week. Among the total, 147 patients have recovered and returned to work, while another 47 are still in quarantine.

None of the Olympic athletes have been infected by the virus so far.(Yonhap)