The New York Times reports:
Industry executives said that in fact the situation had spiraled out of control and that all plant workers needed to leave the plant to avoid excessive exposure to radioactive leaks. If all workers do in fact leave the plant, the nuclear fuel in all three reactors is likely to melt down, which would lead to wholesale releases of radioactive material — by far the largest accident of its kind since the Chernobyl disaster 25 years ago. Reports of an imminent worsening of the problem came after a frantic day and night of rescue efforts focused largely on the No. 2 reactor. There, a malfunctioning valve prevented workers from manually venting the containment vessel to release pressure and allow fresh seawater to be injected into it. That meant that the extraordinary remedy emergency workers have been using to keep the nuclear fuel from overheating no longer worked. As a result, the nuclear fuel in that reactor was exposed for many hours, increasing the risk of a breach of the container vessel and a more dangerous emissions of radioactive particles.
VIDEO: Breaking report by Lawrence O’Donnell.
UPDATE: English-language NHK Tokyo is live-streaming their video reports.