SEOUL, South Korea (AP) — North Korea said Friday it test-fired long-range cruise missiles in waters off its eastern coast a day earlier, adding to a provocative streak in weapons demonstrations as its rivals step up military training.

The US and South Korean militaries didn’t immediately confirm the exercise, which North Korea’s official Korean Central News Agency said were intended to verify the reliability of the missiles and the rapid-response capabilities of the unit that operates those weapons.

The launches would have taken place as the United States and South Korea held a simulated military exercise in Washington aimed at sharpening their response to North Korean nuclear threats.

KCNA said the exercise involved four missiles, which flew for nearly three hours, drawing oval and figure-eight patterns above the sea, and showed that they can hit targets 2,000 kilometres (1,240 miles) away.

North Korea first tested a long-range cruise missile system in September 2021 and has implied they are being developed to be armed with nuclear warheads.

It also test-fired an intercontinental ballistic missile Saturday and a pair of short-range missiles Monday to demonstrate dual ability to conduct nuclear strikes on South Korea and the US mainland.

North Korea said Monday’s short-range launches were a response to the United States flying B-1B bombers to the region for joint training with South Korean and Japanese warplanes on Sunday in a show of force following the North’s ICBM test.

Prior to the ICBM launch, North Korea vowed an “unprecedentedly” strong response over a series of military drills planned by Seoul and Washington. North Korea for decades has described the annual US-South Korea drills as rehearsals for a potential invasion, although the allies say their exercises are defensive in nature.

North Korea is coming off a record year in weapons demonstrations with more than 70 ballistic missiles fired, including ICBMs with potential to reach the US mainland. It also conducted what it described as simulated nuclear attacks against South Korean and US targets in response to the allies’ joint military exercises.

Leader Kim Jong Un doubled down on his nuclear push entering 2023, calling for an “exponential increase” in nuclear warheads, mass production of battlefield tactical nuclear weapons targeting “enemy” South Korea and the development of more advanced ICBMs.

The US Department of Defense and South Korea’s Defense Ministry said the US and South Korean militaries conducted a simulation at the Pentagon on Wednesday that was focused on the possibility of the North Korean use of nuclear weapons. The allies also discussed various adoptions to demonstrate their “strong response capabilities and resolve to response appropriately” to any North Korean nuclear use.

The Americans during the meeting highlighted the Biden administration’s 2022 Nuclear Posture Review, which states that any nuclear attack by North Korea against the United States or its allies and partners is “unacceptable and will result in the end of that regime,” the US Department of Defense said. It was referring to a legislatively mandated document that spells out US nuclear policy and strategy for the next five to 10 years.