North Korea launched a long-range rocket on Wednesday in defiance of its critics abroad, and sources said the launch may have succeeded where earlier attempts had failed.
Later, a Defense Ministry representative told reporters that the launch "looked successful, but whether it has been really successful needs more time to determine."
Japan's chief cabinet secretary, Osamu Fujimura, said North Korea's Unha rocket flew over Okinawa at 10:01 a.m. local time. He could not confirm whether any debris fell on Japanese territory. "The Japanese government regards this launch as an act compromising the peace and stability of the region, including Japan," Fujimura said.
Fujimura said the launch was "completely unacceptable," but he reassured the public that the Japanese government was doing everything possible to ensure national security. "Please go about your daily lives calmly," he said during a briefing.
Japan's NHK television network reported that the rocket's second stage crashed into the sea off the coast of the Philippines as planned, minutes after passing over Okinawa. The key question was whether the third stage successfully reached outer space.
This month, U.S. State Department spokeswoman Victoria Nuland said "a North Korean 'satellite' launch would be a highly provocative act that threatens peace and security in the region." Nuland said such a launch would violate U.N. Security Council resolutions.
North Korea is banned from conducting missile and nuclear tests, under the terms of U.N. sanctions imposed after a series of nuclear weapons tests in 2006 and 2009.
Wednesday's launch follows up on an attempt in April that ended in failure just minutes after liftoff.
North Korea's space effort is a point of prestige for the country's 29-year-old leader, Kim Jong Un, who assumed power after his father, Kim Jong Il, died last December. North Korea has claimed that it successfully launched two previous satellites in 1998 and 2009, but outside experts say there's no sign that anything was ever put into orbit.