An American nuclear submarine visited South Korea late last week, the U.S. Navy has announced, following Washington’s pledge to “constantly” deploy U.S. assets to the peninsula to deter North Korean military aggression.

“The Los Angeles-class fast-attack submarine USS Springfield (SSN 761) arrived in Busan for a scheduled port visit,” U.S. Navy Korea stated on its official Facebook page on Saturday, alongside photos of the submarine’s visit.