US. Indo-Pacific Command has restricted all non-essential travel to South Korea a day after a U.S. service member there tested positive for the coronavirus in the military’s first confirmed case, officials said.

The travel ban applies to all U.S. troops and civilian contractors under INDOPACOM authority, the command announced in a brief Facebook message on Wednesday.

“The number of reported cases of novel coronavirus (COVID-19) continues to rise in the Republic of Korea (ROK),” the Facebook message says. “Effective immediately, Commander, U.S. Indo-Pacific Command, in line with the CDC Travel Health Notice, restricts all nonessential DoD travel to ROK to reduce risks associated with COVID-19.”

No further information was immediately available.

U.S. Forces Korea has been on heightened alert since Monday, when the widow of a retired soldier tested positive for the coronavirus.

Defense Secretary Mark Esper said recently that the commander of U.S. Forces Korea is considering curtailing an exercise with the South Korean military due to concerns about the coronavirus.

As of Sunday, 13 South Korean service members had been diagnosed with the coronavirus, South Korean Defense Minister Jeong Kyeong-doo said at a Pentagon news conference on Monday.

Separately, medical teams determined that two ill soldiers who landed at Fort Hood on Tuesday after returning from South Korea likely had food poisoning or air sickness, not the coronavirus, officials said.

On Jan. 31, the head of INDOPACOM restricted all U.S. troops and Defense Department civilians from traveling to China. All Defense Department personnel that were in China at the time were ordered to leave.

The coronavirus has spread to elsewhere in Asia, Europe and the Middle East, prompting the Department of Defense Education Activity to close 15 schools in South Korea, Italy, Bahrain, and elsewhere through at least Friday, according to Military Times reporter Patricia Kime.

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