North Korea has accused the United States of flying spy planes over the country – and threatened to shoot them down.

That’s according to a statement carried by the official KCNA news agency website on Monday, which quoted North Korea’s Ministry of National Defence.

The statement said that a plane flew into North Korean airspace, quote, “dozens of kilometres over its east sea several times.”

And that: “There is no guarantee that such a shocking accident as the downing of the U.S. Air Force strategic reconnaissance plane will not happen.”

South Korea’s military said North Korea’s claim of airspace violation was false.

“U.S. air surveillance assets conduct routine reconnaissance flights around the Korean peninsula and North Korea’s claim of airspace violation is not true. We strongly urge the North to immediately stop creating tension with these false claims.”

The North Korean statement said that provocative military actions by the U.S. were bringing the Korean peninsula closer to a nuclear conflict.

Sister of North Korean leader Kim Jong Un alleged that the country’s warplanes repelled a U.S. spy plane flying over nearby waters Monday and warned of “shocking” consequences if the U.S. continues reconnaissance in the area.

The United States and South Korea dismissed the North’s accusations and urged it to refrain from any acts or rhetoric that raises animosities.

It’s unclear if North Korea would follow through. It has made numerous similar threats over alleged U.S. reconnaissance activities, but its latest statement came amid heightened animosities over North Korea’s barrage of missile tests earlier this year.

Kim Yo Jong, one of her brother’s top foreign policy officials, claimed that the U.S. spy plane reached into the North’s eastern exclusive economic zone eight times Monday. In a statement carried by state media Monday night, she claimed that the North scrambled warplanes to chase away the U.S. plane.

“A shocking incident would occur in the long run in the 20-40 kilometer section in which the U.S. spy planes habitually intrude into the sky above the economic water zone” of North Korea, Kim Yo Jong said.

Earlier Monday, North Korea’s Defense Ministry accused the U.S. of flying a strategic reconnaissance plane into its “inviolable airspace” several times and warning that approaching aircraft might be shot down.

While the Defense Ministry statement seemed to imply an intrusion into North Korean territorial airspace, Kim Yo Jong accused the U.S. of conducting aerial surveillance over the North’s exclusive economic zone, the area within 200 nautical miles of its territory where it controls rights to natural resources.

Sabrina Singh, deputy Pentagon press secretary, called the North’s claim on the airspace violation “just accusations.”

“The United States, as always, remains committed to safely and responsibly flying, sailing, operating anywhere that international law allows and alongside our allies and partners,” Singh said.

Matthew Miller, a spokesperson for the U.S. State Department, said the United States urges North Korea to refrain from “escalatory actions” and engage in serious diplomacy.

South Korea’s Joint Chiefs of Staff denied that the U.S. had flown any spy plane into North Korean territory. Spokesperson Lee Sung Joon said at a briefing that the U.S. was conducting standard reconnaissance activities in coordination with South Korea’s military.

Later Monday, the South Korea’s Joint Chiefs of Staff said in a second statement that it strongly urges North Korea to stop rhetoric that raises tensions over “normal flight by the Korea-U.S. alliance over open waters.”

Early Tuesday, Kim Yo Jong issued another statement reasserting that intensifying U.S. reconnaissance activities were encroaching on the North’s sovereignty and that the U.S. forces would “experience a very critical flight” if they continue with their illegal intrusions.

Last month an American nuclear-powered cruise missile submarine made a port call at Busan in South Korea.

That came amid air and navy drills being conducted by U.S. and South Korean forces, also involving a U.S. aircraft carrier and heavy bombers.

Less than two weeks ago, North Korea held mass rallies in Pyongyang showing posters with missiles hitting the United States.

Those marked the 73rd anniversary of the start of the Korean War.

State-run television KRT said people were heard shouting slogans vowing a “war of revenge.”

The rallies were held amid concerns Pyongyang could soon conduct another launch of its first military spy satellite to boost monitoring of U.S. military activities.

That’s after its first attempt ended in failure on at the end of May.

Earlier this year, tensions on the Korean Peninsula rose sharply as the pace of North Korean weapon tests and U.S.-South Korea joint military exercises have intensified. North Korea has test-fired nearly 100 missiles since the start of 2022 as Kim Jong Un expands a nuclear arsenal he apparently sees as his strongest guarantee of survival.

The United States stations about 28,500 troops in South Korea as deterrence against potential aggression by North Korea.