March 17, 2011 at 6:30 PM ET
U.S. officials have told NBC News that they're seeing a disparity between Japanese radiation readings and the readings they've been getting from military monitors.
Concerns about the release of radiation from Japan's stricken nuclear plants at the Fukushima Dai-ichi complex began with data collection on the aircraft carrier USS Ronald Reagan. On Monday, the U.S. Seventh Fleet relocated its ships and aircraft out of the downwind direction after crew members returning to the carrier were found to have picked up low levels of radioactive contamination. The personnel were scrubbed down with soap and water, then declared contamination-free.
Since then, the data on radiation releases suggest a range of outcomes, going all the way up to "dire," the officials said. They spoke with NBC on condition of anonymity because they were not authorized to discuss the findings publicly.
NBC's sources said the Japan nuclear site and its surroundings are being monitored by a variety of U.S. aircraft, including:
Intelligence experts also tell NBC News that the United States has a network of ground-level stations around the world that monitor radiation and can backtrack to calculate how much has been dispersed from a specific site.
Officials said several agencies are analyzing the data, including the Department of Energy's Nuclear National Security Administration and the CIA.
Tip o' the Log to NBC News' Robert Windrem and Courtney Kube.
More on the radiation situation in Japan:
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