A missile fired from North Korea landed in the sea off the Japanese coast, in a launch condemned as "outrageous" and a danger to peace in the region.
Two ballistic missiles were fired simultaneously Wednesday, although one of the projectiles exploded immediately after launch, the South Korean Defence Ministry said.
The second missile landed about 250 kilometres off the Oga peninsula on the west coast of Japan, according to Defence Minister Gen Nakatani. Tokyo said the missile had landed inside the country's Exclusive Economic Zone (EEZ).
The launch was an "outrageous act and a grave threat to our country's national security," Japanese Prime Minister Shinzo Abe said.
"It was a clear violation of United Nations Security Council resolutions. We lodged a strong protest with North Korea," he told reporters.
The UN Security Council, which held an emergency meeting Wednesday, was unable to agree on a statement over the launch, however, there were "strong condemnations across the board," said Samantha Power, US ambassador to the UN.
Power said she was confident the Security Council would come together to swiftly condemn the test, which she called "another effort by [North Korea] to enhance its menacing capabilities."
Koro Bessho, Japanese ambassador to the UN, warned that the missile reaching Japan's EEZ "was a new step in [North Korea's] development of nuclear and missile capabilities."
This new dimension was "something the [Security] Council should take extremely seriously," said Peter Wilson, British deputy ambassador to the UN.
Liu Jieyi, Chinese ambassador to the UN, called for de-escalation.
"Nothing should be done to exacerbate tension on the Korean peninsula - I think there is a real risk," Liu told reporters.
UN Secretary General Ban Ki-moon condemned the launch, said Stephane Dujarric, his spokesman, noting that "such actions seriously undermine regional peace and stability."
The launch touched off another wave of criticism from the West, following several such actions by the isolated regime in recent months.
North Korea previously fired three ballistic missiles on July 19, including two mid-range Rodong missiles and a shorter-range Scud missile.
NATO Secretary General Jens Stoltenberg "strongly" condemned the latest missile test, noting that the country's "persistent provocative behaviour" is of "deep concern and undermines international security."
Wednesday's launch will "serve no purpose other than heighten tensions" on the peninsula, the European Union's diplomatic service warned in a statement.
Pyongyang is "clearly violating once more its international obligations," the statement said, noting that the move will "threaten the peace and security of the wider region."
Meanwhile, Germany was to summon the North Korean ambassador to the Foreign Ministry in Berlin to discuss the issue.
The missile test was a "dangerous act of provocation" and represented a new quality in North Korea's testing programme because of its proximity to Japanese waters, German Foreign Office spokesman Martin Schaefer said.
The Rodong intermediate-range ballistic missiles were launched near the western North Korean city of Hwangju. One flew about 1,000 kilometres toward Japan, the Defence Ministry in Seoul said.
The launches follow threats from Pyongyang over a new US missile defence system set to be deployed in South Korea.
In July, South Korea and the United States agreed to deploy the system in South Korea's Seongju county to counter Pyongyang's developing missile threats, the Yonhap news agency reported.
The Terminal High Altitude Area Defense (THAAD) system is designed to shoot down a ballistic missile at heights of 40-150 kilometres, the report said.
The deployment in South Korea is scheduled for late 2017, it said.
Following the decision to deploy THAAAD, North Korea warned that it would take a "physical counter-action" against the anti-missile shield, Yonhap reported.