When the data differ, the on-going summary defers provisionally to the Japanese regulator.
Here is an excerpt dealing with the apparent rupture of the suppression chamber of reactor 2 on March 15 after its cooling power failed on the 14th and its water in the torus boiled.
From the "Fukushima Accident 2011" at World-Nuclear.org, last updated today (here):
After the hydrogen explosion in unit 1, some radioactive caesium and iodine were detected in the vicinity of the plant, indicating fuel damage. This material had been released via the venting. Further I-131 and Cs-137 and Cs-134 were apparently released during the following two weeks, particularly following the apparent rupture of suppression chamber of unit 2 on 15th. The caesium was at low levels (about two orders of magnitude less than the iodine). The hydrogen explosion in unit 4 involving the spent fuel pond on 15th apparently added to the airborne radionuclide releases.
