FILE - In this March 11, 2011 file photo released by Tokyo Electric Power Co., waves of tsunami come toward tanks of heavy oil for the Unit 5 of the Fukushima Dai-ichi nuclear complex in Okuma, Fukushima Prefecture, northeastern Japan. Japanese nuclear regulators trusted that the reactors at Fukushima Dai-ichi were safe from the worst waves an earthquake could muster based on a single-page memo from the plant operator nearly a decade ago. The towering waves unleashed by the magnitude-9.0 earthquake on March 11 destroyed backup generators for several reactors' cooling systems, and the nuclear cores in three reactors melted, sparking the worst atomic crisis the world since Chernobyl. Workers have yet to bring the plant under control more than two months later. (AP Photo/Tokyo Electric Power Co., File) EDITORIAL USE ONLY
TOKYO (AP) — The emergency command center at Japan's stricken nuclear plant shook violently when hydrogen exploded at one reactor and the plant chief reacted by shouting, "This is serious, this is serious," reveal videos of the crisis as it happened last year.
Tokyo Electric Power Co. initially refused to release the videos, but the company is now under state control and it was ordered to do so. The footage seen Monday was mainly of teleconferences between company headquarters in Tokyo and staff at the Fukushima Dai-ichi nuclear plant, after the March 11, 2011, tsunami caused critical damage to its reactors.
In the videos, then-plant chief Masao Yoshida complained about phone calls to the prime minister's office not getting through and showed frustration as he fought the government's nuclear safety officials interfering with technical suggestions that didn't fit the plant's conditions.
Around 11 a.m. on March 15, Yoshida screamed to officials at Tokyo headquarters: "The headquarters! This is serious, this is serious. The No. 3 unit. I think this is hydrogen explosion. We just had an explosion."
In the video's background, other officials shout questions, asking for radiation levels and other data.
The videos also included conversations showing communication problems between the plant and the government, workers' lack of knowledge in emergency steps and delays in effort to inform outsiders about the risks of leaking radiation.
Also on March 15, the videos showed then-Prime Minister Naoto Kan bursting into TEPCO's Tokyo office, rebuking officials and demanding they work harder. The portion of his visit has no sound. While Kan spoke for 20 minutes, operations at Fukushima Dai-ichi seemed halted, with officials and workers there, as well as TEPCO executives in Tokyo, sitting straight and quietly listening to him.
TEPCO made a 90-minute video of selected clips available for download, while journalists who registered beforehand were allowed to see 150 hours of coverage. The content was heavily edited, with white shades shielding workers' faces and nametags and beeps masking voices and other sound.
The massive earthquake and tsunami that hit northeast Japan knocked out the plant's cooling systems. The cores of three reactors melted, releasing large amounts of radiation, and explosions of hydrogen gas badly damaged two reactor buildings.
It was the world's second worst nuclear accident after Chernobyl, residents whose homes were nearest the plant have not been allowed to return and cleanup at the site may take decades.
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