North Korea has fired two short-range ballistic missiles toward its east coast in the direction of Japan, following joint South Korean and US missile drills and the return of a US aircraft carrier to the region in response to the North’s recent missile tests.

The missile launch on Thursday was the sixth in 12 days and the first since North Korea fired an intermediate-range missile (IRBM) over Japan on Tuesday.

The launch was reported by South Korea’s Joint Chiefs of Staff and the Japanese government.

The Japan Coast Guard said the missiles appeared to have landed already.

“This is the sixth time in the short period just counting the ones from the end of September,” Japanese Prime Minister Fumio Kishida said on Thursday.

“This absolutely cannot be tolerated.”

The launch came about an hour after North Korea condemned the US for talking to the United Nations Security Council about Pyongyang’s “just counteraction measures of the Korean People’s Army on south Korea-US joint drills”.

In a statement released by the reclusive nation’s foreign ministry, North Korea also condemned Washington for repositioning a US aircraft carrier in the waters off the Korean peninsula, saying it posed a serious threat to the stability of the situation.

The USS Ronald Reagan and its strike group of accompanying warships was abruptly redeployed this week after South Korea and the US military conducted rare missile drills east of North Korea.

Nuclear-armed North Korea test-fired an intermediate-range ballistic missile farther than ever before on Tuesday, sending it soaring over Japan for the first time in five years and prompting a warning for residents there to take cover.

South Korean and American troops fired a volley of missiles into the sea in response, South Korea’s Joint Chiefs of Staff said on Wednesday, and the allies earlier staged a bombing drill with fighter jets in the Yellow Sea.

The military separately confirmed that a South Korean Hyunmoo-2 missile failed shortly after launch and crashed during the drill, but that no one was hurt.

Footage shared on social media by a nearby resident and verified by Reuters showed smoke and flames rising from the military base.

The fire was caused by burning rocket propellant, and although the missile carried a warhead, it did not explode, South Korea’s military said.

It apologised for causing residents to worry.

On Wednesday, the US accused China and Russia of enabling North Korean leader Kim Jong-un by blocking attempts to strengthen UN Security Council sanctions on Pyongyang over its nuclear weapons and ballistic missile programs.

– with AAP