North Korea threatened on Wednesday to shoot down any US spy planes violating its airspace to monitor an imminent rocket launch, as a think-tank cautioned that any international over-reaction to the event could spark a war.
The North's warning on state radio followed its accusations Tuesday that US planes had stepped up flights over the northeast where the Musudan-ri missile site is located.
The North has announced it will launch a communications satellite some time between April 4-8.
The United States, South Korea and Japan call this a pretext for a "provocative" test of a long-range ballistic missile in violation of UN resolutions. They say they will report the launch to the Security Council.
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On Wednesday the North's Korean Central Broadcasting Station denounced US spy planes for monitoring preparations.
"Should the US imperialist racketeers dare to intrude espionage planes into our territorial sky, interfering with our preparations for a satellite launch for peaceful purposes, our revolutionary forces will shoot them down unsparingly," it said.
