A U.S. military satellite has detected "imminent signs" of a fresh North Korean nuclear test, CNN quoted a senior Defense Department official as saying Monday.
The Pentagon official said the satellite last weekend photographed a tarpaulined tunnel entrance at a nuclear test site in Punggye-ri, North Hamgyong Province.
This could be an attempt to prevent the surveillance satellite from spying on the process of preparing for an underground nuclear test.
The final preparatory stage of a nuclear test would be to fill up the tunnel entrance.
The same day, Foreign Minister Yun Byung-se met with EU foreign minister Catherine Ashton in New York. "If North Korea carries out a fresh nuclear test or fires mid-range missiles, the international community should slap strong sanctions on Pyongyang enough to put the kibosh on the issue," Yun said. He called for a new type of sanction to bring an end to the North's nuclear program.
Seoul has stepped up 24-hour surveillance, believing that a fourth North Korean nuclear test is imminent.
"We can't rule out that the North is bluffing," a government official said. "But it seems they've finished preparations for a nuclear test and are now just waiting for the regime to give the go-ahead."