North Korea has launched a long-range rocket carrying what it has said is a satellite, South Korea’s defence ministry says.
The launch is in defiance of United Nations sanctions barring it from using ballistic missile technology.
United States Strategic Command said it had detected what it called a missile entering space, appearing to quash earlier media reports indicating it might have failed during flight.
Secretary of State John Kerry said the US would work with the UN Security Council on “significant measures” to hold North Korea to account.
The North American Aerospace Defence Command said it had tracked the missile and determined it was not a risk to the US.
North Korea had notified UN agencies it planned to launch a rocket carrying an Earth observation satellite, triggering opposition from governments that see it as a long-range missile test.
The rocket was launched on a southward trajectory as planned, passing over Japan’s southern Okinawa islands, Japan’s NHK reported.
Japanese Prime Minister Shinzo Abe described the launch as “absolutely unacceptable”.
The United States, Japan and South Korea have requested an emergency meeting of the United Nations Security Council on Sunday to discuss the rocket launch, council diplomats said.
The North has insisted its space program is purely scientific in nature, but the US and allies, including South Korea, have said its rocket launches were aimed at developing an inter-continental ballistic missile capable of striking the US mainland.
It had planned to launch the rocket later this month, but brought the date forward.
Last month, North Korea tested a nuclear device for the fourth time, although the United States and other governments have expressed doubt over the North’s claim that it exploded a hydrogen bomb.
The country is believed to be working on miniaturising a nuclear warhead to mount on a missile, but many experts say it is some time away from perfecting such technology.
It has shown off two versions of a ballistic missile resembling a type that could reach the US west coast, but there is no evidence the missiles have been tested.