The officials said members of the delegation learned of the positive result as they arrived in Guam on Friday.
It is not clear if the person had any direct contact with Esper. Under standard protocols the individual would be tested again. CNN has not learned any details on whether further testing has taken place.
The Pentagon did not respond immediately to CNN’s request for comment.
It is also unclear how the situation will impact travel plans for the secretary’s return to the US, the officials said.
Esper embarked on the trip to the Indo-Pacific region last week, which included stops in Hawaii and Palau. The secretary is currently in Guam.
Esper posted a video on Twitter Friday showing him laying a wreath in the waters of Palau for fallen service members from World War II. The secretary also posted a photo Thursday night of him meeting with sailors aboard the USS Essex. Esper was wearing a mask in the photos and video.
This story is breaking and will be updated.
