SEOUL, South Korea (AP) _ Three days after North Korea announced that it had successfully launched a ``scientific'' satellite into Earth's orbit, South Korea said Sunday it still could not verify the claim.

Chief presidential spokesman Park Jie-won said South Korea had not yet determined whether North Korea fired a missile or launched a satellite.

``We're closely cooperating and exchanging information with the United States and Japan to determine the truth of the North Korean claim,'' he said.

On Friday, North Korea denied that it launched a ballistic missile this week, saying it successfully fired into orbit its first artificial satellite, which it described as ``scientific.''

But U.S. and Japanese defense officials said the launch was the test-firing of a ballistic missile that sailed over northern Japan and crashed into the Pacific Ocean.

North Korea said reports of a missile firing were wrong.

``Some people ... suspected it to be a ballistic missile launching test, expressed some apprehensions and described it as a serious event,'' the Foreign Ministry said in a statement.

North Korea said the satellite was circling the earth transmitting revolutionary hymns praising the late President Kim Il Sung and his heir and son, Kim Jong Il.

But South Korean officials said Sunday that they failed to detect such transmissions.

``All 11 monitoring stations throughout the country could not detect any signals,'' one Telecommunications Ministry official said on condition of anonymity.