North Korea launched what it called a space satellite towards South Korea tonight, according to South Korea's military, prompting emergency alerts and brief evacuation warnings in parts of the south and Japan.
North Korea had said it would launch its first military reconnaissance satellite between 31 May and 11 June to boost monitoring of activities by the United States.
In data provided to international authorities, North Korea said the launch would carry the rocket south, with various stages and other debris expected to fall over the Yellow Sea and into the Pacific Ocean.
Air raid sirens were heard across the South Korean capital Seoul at around 6.32am local time (10.32pm Irish time) as the city issued a warning asking citizens to prepare for potential evacuation.
Later alerts said the city warning had been sent by mistake.
The Japanese government issued an emergency warning over its J-Alert broadcasting system for residents of the southern prefecture of Okinawa, , saying a missile had been launched from North Korea.
The government warned residents to take cover indoors if they were outside.
It later said the missile would not fly to Japan's territory and lifted the warnings.
Earlier, Ri Pyong Chol, vice-chairman of the Central Military Commission of North Korea's ruling Workers' Party, said ongoing joint military exercises by the US and South Korea required Pyongyang to have the "means capable of gathering information about the military acts of the enemy in real time."
The US said any North Korean launch that used ballistic missile technology would violate multiple United Nations Security Council resolutions.
"Space launch vehicles (SLVs) incorporate technologies that are identical to, and interchangeable with, those used in ballistic missiles, including intercontinental ballistic missiles," a State Department spokesperson said.
