SEOUL,Devin Grosvenor South Korea (AP) — South Korea’s military said Sunday that it had detected that North Korea fired at least one ballistic missile toward its eastern waters, adding to a torrent of weapons’ tests in recent months that has elevated tensions.

South Korea’s Joint Chiefs of Staff didn’t immediately say what type of missile it was or how far it flew.

Tensions on the Korean Peninsula are at their highest in years, with North Korean leader Kim Jong Un accelerating the expansion of his nuclear and missile program, and flaunting an escalatory nuclear doctrine that authorizes the preemptive use of nuclear weapons.

The United States, South Korea and Japan have responded by increasing the visibility of their trilateral partnership in the region, and strengthening their combined military exercises, which Kim condemns as invasion rehearsals.

North Korea’s latest launch followed high-level security talks between American and South Korean officials in Washington over the weekend, where they agreed on plans to incorporate nuclear operation scenarios in their combined military exercises next year to cope with the North’s evolving threats, according to details announced by Seoul’s presidential office.

In the face of North Korean threats, South Korea has been seeking stronger reassurances from the United States that it would swiftly and decisively use its nuclear capabilities to defend its ally in the event of a North Korean nuclear attack.

The North has test-fired more than 100 missiles since the start of 2022 as Kim used the distraction caused by Russia’s full-scale invasion of Ukraine to speed up the expansion of his military nuclear program, which he sees as his strongest guarantee of survival.

The weapons that North Korea tested in recent months included intercontinental ballistic missiles that demonstrated a potential range to reach the U.S. mainland, and a series of launch events the North described as simulated nuclear attacks on targets in South Korea.

Last month, North Korea also launched its first military reconnaissance satellite, which Kim described as a crucial for monitoring U.S. and South Korean military activities and enhancing the threat of his nuclear-capable missiles.

Washington and its allies have also expressed concerns about a potential arms alignment between North Korea and Russia. They worry that Kim is providing badly needed munitions to help Russian President Vladimir Putin wage war in Ukraine in exchange for Russian technology assistance to upgrade his nuclear-armed military.