A U.S. soldier facing disciplinary action at home “willfully and without authorization" slipped across the inter-Korean border into North Korea on Tuesday and was apparently taken into custody, U.S. officials said.

The incident is the latest headache for the U.S. as it attempts to grapple with an unprecedented spate of missile launches — including the launch of two weapons early Wednesday — by the nuclear-armed country.

U.S. Defense Secretary Lloyd Austin confirmed that a service member had willingly crossed the Military Demarcation Line separating the two Koreas without permission during a tour and that he was likely being detained by the North.