North Korea has begun activating observation cameras and radars around the coastal site in the northeast, a South Korean report said Sunday, as the communist country prepares to launch a rocket in defiance of international warnings.

The top part of the rocket mounted at the Musudan-ri launch pad has also been uncovered, the Yonhap news agency reported, citing an unnamed South Korean official. The report did not say whether a satellite was mounted on top.

South Korea's Defense Ministry and the National Intelligence Service, the country's main spy agency, declined to confirm the report.

Click to view photos | Satellite image of the launch area

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North Korea has said it intends to send a communications satellite into space on board a multistage rocket sometime over the next several days, despite calls from the U.S., Japan and others to refrain from a launch they say is banned under a U.N. Security Council resolution barring the North from ballistic missile activity.

Preparations for sending "an experimental communications satellite" into space were complete, North Korea's state-run media said Saturday, announcing: "The satellite will be launched soon."

But high winds in the area may have forced a delay. On Sunday, North Korean state radio reported light winds and clear skies in the northeast. South Korea's weather agency also predicted good weather in the area.

Leaders from the five nations negotiating to disarm the North have tried in the past few weeks to stop the launch. The U.S., South Korea, Japan and others suspect the launch is a guise for testing the regime's long-range missile technology — a step toward eventually mounting a nuclear weapon on a missile capable of reaching Alaska and beyond.

"It's an act that causes a serious concern for the stability and peace on the Korean peninsula and Northeast Asia," South Korean Unification Minister Hyun In-taek said Sunday during a ministry meeting. "I believe such an action will not also benefit North Korea, too."

President Barack Obama said the launch would be "provocative" and would prompt the U.S. to "take appropriate steps to let North Korea know that it can't threaten the safety and security of other countries with impunity."

Japan's foreign minister, Hirofumi Nakasone, said Saturday it would be "regrettable" if Pyongyang fails to heed its neighbors' appeals.

Even President Hu Jintao of China, North Korea's chief ally, agreed during talks Friday with South Korean President Lee Myung-bak that the launch would "negatively affect peace and stability in Northeast Asia," Lee's office said.

U.N. Security Council diplomats say a draft resolution now circulating could reaffirm and tighten enforcement of the demands and sanctions of a resolution passed after North Korea conducted a nuclear test on 2006.

Taking no chances, Japan deployed warships and missile interceptors off its northern coast to shoot down any wayward parts the North said might litter the area as the rocket passes over the country.

North Korea has warned Japan any attempt to intercept the satellite would mean war and has threatened to shoot down American U-2 spy planes broaching its airspace.

Russia scrambled fighter jets to the Far East and put its troops there on alert, Sergei Roshcha, an aide to regional commander Lt. Gen. Valery Ivanov, told the Russian news agency Interfax.

The military is tracking the missile path and will not let any fragments fall on Russian territory, Vesti television said, citing a source in the Russian Armed Forces' General staff.

As South Korea's president huddled with his Cabinet, his government urged citizens working at joint economic zones in North Korea and in Pyongyang to return home because of the "grave" tensions on the peninsula. More than 600 South Koreans left the North on Saturday, the Unification Ministry said.

A South Korean who works at a factory in the northern border town of Kaesong remained in North Korean custody after being detained Monday for allegedly denouncing the North's political system and inciting female North Korean employees to flee the communist country.

North Korea is also holding two American journalists accused of crossing into the country illegally from China and engaging in "hostile acts." Euna Lee and Laura Ling, reporters for former Vice President Al Gore's Current TV media venture, will be indicted and put on trial, Pyongyang has said.