North Korea has launched what was described as a space launch vehicle, after announcing a plan to put its first military spy satellite into orbit. Sirens were heard across Seoul early on Wednesday as the city issued a warning asking citizens to prepare for potential evacuation. However, the interior ministry later said the warning was sent in error, and the military confirmed the launch would have no impact on the capital. The Japanese government also briefly 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. It later confirmed the missile did not fly over Japanese territory. North Korea had said it would launch its first military reconnaissance satellite between 31 May and 11 June to boost monitoring of US activities, drawing a threat from Japan to destroy any North Korean missile that violates its territory. Japan’s defence ministry said in a statement: “We will take destructive measures against ballistic and other missiles that are confirmed to land in our territory.” Analysts say a military satellite would enhance North Korea’s surveillance capability and improve its ability to strike targets in the event of war. A satellite launch by North Korea is a violation of UN security council resolutions that ban the country from using ballistic technology because it is regarded as a cover for missile tests.