SEOUL, South Korea — The South Korean and U.S. militaries have postponed their annual drills out of concerns over the virus outbreak.

Thursday’s announcement came after South Korea reported 21 cases of a new coronavirus in its military and the U.S. military reported one case among its 28,500 troops in South Korea.

South Korea has already suspended some unilateral field training, placed 9,570 troops under quarantine and banned most of its enlisted soldiers from leaving their bases.

The U.S. military closed some amenities at several bases and is urging its personnel to avoid handshakes and large gatherings if possible.  

The announcement was jointly made by South Korea's Joint Chiefs of Staff and the U.S. military in South Korea.

"In light of the ROK government’s declaration of the highest alert level 'severe' on COVID-19, the ROK-US Alliance made the decision to postpone the combined command post training for the ROK-US Combined Forces Command until further notice," the statement said. "The containment efforts for COVID-19 and the safety of the ROK and US service members were prioritized in making this decision."

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South Korea said Thursday it had more than 1,500 cases of the coronavirus that causes the COVID-19 illness, the second-most behind China. Most cases were in the country's fourth-biggest city, Daegu, where the outbreak has hit hardest. But there are signs the virus is spreading with dozens of cases in Seoul and South Korea's second-largest city, Busan. 

"Despite the postponement of combined training, the ROK-US alliance remains committed to providing a credible military deterrence and maintaining a robust combined defense posture to protect the ROK against any threat," the statement said.

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