A TV screen shows a file image of a North Korean missile launch during a news program at the Seoul Railway Station in Seoul, South Korea, on May 17, 2024. Ahn Young-joon / AP

North Korea fired suspected short-range ballistic missiles off its east coast on Friday, South Korea's military said, a day after South Korea and the U.S. flew powerful fighter jets in a joint drill that the North views as a major security threat.

South Korea's Joint Chiefs of Staff said the weapons launched from the North's east coast Wonsan region traveled about 185 miles before landing in the waters between the Korean Peninsula and Japan. Japan's Chief Cabinet Secretary Yoshimasa Hayashi said a North Korean missile landed outside Japan's exclusive economic zone.

South Korea's Joint Chiefs of Staff statement called the launches "a clear provocation" that threatens peace on the Korean Peninsula. It said South Korea will maintain a firm readiness to repel potential aggressions by North Korea in conjunction with the military alliance with the United States.

In recent months, North Korea has extended its run of weapons testing as part of its efforts to enlarge and modernize its arsenal while diplomacy with the United States and South Korea remains dormant. Last week, North Korean leader Kim Jong Un supervised the test firing of a new multiple rocket launch system, according to the North's state media.

North Korea says it's been forced to boost its nuclear and missile programs to deal with U.S.-led hostilities. North Korea cites expanded U.S.-South Korean military training, which it calls an invasion rehearsal.

Many foreign experts say North Korea uses its rivals' military drills as a pretext for building a larger weapons arsenal in the belief that it would boost its leverage in future diplomacy with the U.S.

On Thursday, two South Korean F-35As and two U.S. F-22 Raptors were mobilized for combined aerial exercises over the central region of South Korea. North Korea is extremely sensitive to the deployment of sophisticated U.S. aircraft.

Earlier Friday, Kim's sister and senior official Kim Yo Jong said North Korea's recent weapons tests were part of the country's five-year arms buildup plan launched in 2021. She said the recently tested weapons are designed to attack Seoul, the South Korean capital, and denied outside speculation that the tests were meant to display weapons that North Korea plans to export to Russia to use in its war with Ukraine.

"We don't conceal the fact that such weapons will be used to prevent Seoul from inventing any idle thinking," Kim Yo Jong said in a statement carried by state media.

South Korea's Unification Ministry, which deals with North Korea, responded that it is fully ready to repel any military threats from North Korea in conjunction with its military alliance with the United States. Deputy ministry spokesperson Kim Inae also said that "illegal" arms deals between North Korea and Russia must be stopped immediately.

Agence France-Presse notes that Seoul claimed in March that Pyongyang had sent some 7,000 containers of arms to Russia for use in Ukraine since roughly July 2023.

Experts say North Korea wants a range of military aid from Russia in return, such as satellite technology and the upgrading of its Soviet-era military equipment.

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