SEOUL, South Korea (AP) — A nuclear-propelled U.S. submarine has arrived in South Korea in the second deployment of a major U.S. naval asset to the Korean Peninsula this month, South Korea’s military said Monday, adding to the allies' show of force to counter North Korean nuclear threats.

The USS Annapolis arrived at a port on Jeju Island about a week after the USS Kentucky docked at the mainland port of Busan.

The Kentucky was the first U.S. nuclear-armed submarine to come to South Korea since the 1980s. North Korea reacted to its arrival by test-firing ballistic and cruise missiles in apparent demonstrations that it could make nuclear strikes against South Korea and deployed U.S. naval vessels.

In between those launches, North Korea’s defense minister issued a veiled threat insisting the Kentucky’s docking in South Korea could be grounds for the North to use a nuclear weapon against it. North Korea has used similar rhetoric before, but the statement underscored how much relations are strained now.

The Annapolis, whose main mission is destroying enemy ships and submarines, is powered by a nuclear reactor but is armed with conventional weapons. The Annapolis mainly docked at Jeju to load supplies, but Jang Do Young, a spokesperson of South Korea’s navy, said the U.S. and South Korean militaries were discussing whether to arrange training involving the vessel.

Meanwhile, North Korea remained publicly silent on an American soldier, Pvt. Travis King, who crossed the border last Tuesday. U.S. officials have expressed concern about his well-being and said North Korea has been ignoring their requests to provide basic information about King, including where he’s being detained and what his condition is.

Analysts say North Korea wait weeks or even months to provide meaningful information about King to maximize leverage and add urgency to U.S. efforts to secure his release. Some say North Korea may try to wrest concessions from Washington, such as tying his release to the United States cutting back its military activities with South Korea.

The United States and South Korea have been expanding their combined military exercises and increasing regional deployments of U.S. strategic assets like bombers, aircraft carriers and submarines in a show of force against North Korea, which has test-fired around 100 missiles since the start of 2022.