North Korea said its second attempt to launch a spy satellite into orbit failed on Thursday, but vowed to try again in October, state media reported.

Its first attempt in May also ended in failure when the new Chollima-1 rocket crashed into the sea.

The nuclear-armed country is seeking to put its first military spy satellite into orbit, saying it is planning a fleet of satellites to monitor the movements of US and South Korean troops.

The first and second phases of the missile’s flight took place smoothly, but the launch failed due to a fault in the emergency firing system during the third phase of the flight, KCNA said.

The launch prompted an emergency warning in Japan shortly before 4 a.m. local time via the J-alert broadcasting system, telling residents of the southernmost prefecture of Okinawa to take cover indoors.

About 20 minutes after the alert, the Japanese government followed up with a notification that the missile had crossed into the Pacific Ocean and lifted the emergency warning.

In a televised news conference, Japanese Chief Cabinet Secretary, Hirokazu Matsuno, said the repeated missile launches posed a threat to regional security.

Seoul, Tokyo, and Washington condemned the May launch as a provocation and a violation of UN Security Council resolutions banning North Korea’s use of ballistic missile technology.

South Korea recovered parts of that failed missile, including the satellite payload, which it said did not appear to have a military capability.

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