If there's one thing the Japanese government learned on Saturday -- the first of a five-day launch period for a North Korean rocket -- it's that the government's emergency information network works.
At 12:16 p.m. local time, terminals at government agencies, municipalities and media organizations across Japan flashed news from the government: "North Korea appears to have launched a projectile." Almost immediately TV stations broke into programming to deliver the news and soon after it flashed around the world.
Too bad North Korea hadn't actually launched anything. Five minutes later the same network was used to retract the warning.
The error was blamed on a misunderstanding between military staff. A radar station near Tokyo had detected something over the Sea of Japan, which separates the two countries and over which the rocket was expected to fly, and this was relayed to Japan's Air Defense Command. But there, according to local media reports, it was mistaken for data from a U.S. early warning satellite and passed on to the Defense Agency and central government and the alert was issued.
The incident was an embarrassment for the Japanese government and has done nothing to calm nerves in Japan ahead of the launch.
"We caused a great deal of trouble to the Japanese people," said Defense Minister Yasukazu Hamada. "I want to apologize to the people from my heart."
North Korea has said it plans to launch a satellite sometime between April 4 and 8 during an 11 a.m. to 4 p.m. window each day. According to information provided to the international maritime and aviation agencies the first stage of the three-stage rocket is expected to fall into the Sea of Japan before the rocket flies over Japan and the second stage drops into the Pacific Ocean.
Japan, South Korea and the U.S. suspect the launch is actually a missile test and Japan has set up a complex monitoring network.
Three Aegis missile destroyers are stationed off the coast, radar facilities are watching the skies, airborne early warning aircraft are monitoring from the sky and data is being fed from a U.S. military satellite. The government is hoping to use the data to track the rocket and, if it appears to be deviating from its course and threatening Japan, shoot it down. Patriot missile batteries have been stationed at five places in Japan, including central Tokyo, for just such an eventuality.
The computer network that was used Saturday, called Em-Net, was established to relay emergency information from the central government to regional governments across Japan after a previous missile launch in 1998. While the basis for Saturday's alert turned out to be false information the warning was real and was relayed quickly -- albeit by TV stations and municipalities that had been expecting it for more than an hour.
Earlier in the day a warning was erroneously issued to residents in northern Japan, over which the rocket is expected to fly, via a local public-address system. That too was attributed to a misunderstanding in information received from the central government.