The pictures did not reveal any typical signs of a nuclear test such as craters or landslides, the Yonhap news agency reported.

It quoted Vice Science Minister Park Young-Il as saying that the satellite, launched from Russia in July, had been gathering information on the North since October 3, when Pyongyang announced it would carry out the test.

Bad weather had prevented photos of the site in question before October 16, Park said.

Officials have been under fire from the press and the opposition over the inability of the 263 billion won (274 million dollar) Arirang 2 satellite and other sources to have provided information about the test.

The head of South Korean intelligence reportedly told parliament there were "no signs" of a test -- just 30 minutes before it occurred.

Both South Korea and Japan have said that no unusual amounts of radiation had been found to confirm that a nuclear weapon test had occurred. But the United States said air samples did indicate an atom bomb had been detonated.

earlier related report
South Korea's defense chief offers to resign
Seoul (AFP) Oct 24 - South Korean Defense Minister Yoon Kwang-Ung has offered to resign, the presidential spokesman said Tuesday, just two weeks after North Korea conducted a nuclear weapons test. "Minister Yoon has offered to resign. President Roh Moo-Hyun has yet to make a decision on whether to accept his resignation," presidential spokesman Yoon Tae-Young told AFP.

The spokesman did not elaborate on the reason for the defense chief's resignation offer or whether it was linked to the October 9 test. The defense ministry refused to comment.

Yonhap news agency, quoting an unnamed source at Roh's office, said Yoon offered his resignation late Monday when he met President Roh to report on the outcome of annual US-South Korean defense ministers' talks in Washington.

"I think I have wrapped up what I am supposed to do," Yoon was quoted as telling Roh.

Yoon told a group of South Korean journalists late Tuesday that the President had "just listened" to him, adding that he would be in office until early next month, according to Yonhap.

During the talks last Friday, Washington promised Seoul "assurances of firm US commitment and immediate support" in defense matters, while repeating the annual pledge to use the US nuclear umbrella to deter threats.

Yonhap said Yoon's resignation is likely to be accepted. It also said Roh was considering conducting a partial cabinet reshuffle next week which would also affect Foreign Minister Ban Ki-Moon.

Ban becomes the United Nations secretary-general on January 1.

Song Min-Soon, chief presidential security aide, and Vice Foreign Minister Yu Myung-Hwan were touted as strong candidates to replace Ban.

Yonhap said Yoon could replace Song or head the country's main spy agency, the National Intelligence Service.

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