Three cases of the foot-and-mouth disease have been reported at cattle farms in Cheongju, North Chungcheong province, prompting authorities to raise the quarantine level from the lowest "attention" to "caution" on the four-tier scale.

According to the agriculture ministry on Thursday, the disease was confirmed at two farms Wednesday night, followed by a third farm nearly two kilometers away on Thursday morning. They are the first to be reported in the country since January 2019.

Health authorities raised the quarantine level by a notch after an initial testing showed that the genotype of the latest cases matched the vaccine that had been expanded in use recently.

Under the quarantine level "caution," livestock markets in the cities of the affected farms and those in nearby regions will be shut down.

Authorities will cull more than 450 animals at the farms, while restricting the movements of workers and vehicles at farms breeding hoofed and even-toed mammals nationwide to within their regions through 12:00 a.m. Saturday.

Sterilization will begin and vaccinations offered to farms in Cheongju and seven nearby cities and counties.