radiated from the atomic explosion.

C. Secondary fires, i.e., those fires resulting from the collapse of
buildings, damage to electrical systems, overturning of stoves, and other
primary effects of the blast.

D. Spread of the original fires (B and C) to other structures.

The casualties sustained by the inhabitants of both cities were due to:

A. "Flash" burns, caused directly by the almost instantaneous radiation of
heat and light at the moment of the explosion.

B. Burns resulting from the fires caused by the explosion.

C. Mechanical injuries caused by collapse of buildings, flying debris,
and forceable hurling - about of persons struck by the blast pressure
waves.

D. Radiation injuries caused by the instantaneous penetrating radiation
(in many respects similar to excessive X-ray exposure) from the nuclear
explosion; all of these effective radiations occurred during the first
minute after initiation of the explosion, and nearly all occurred during
the first second of the explosion.

No casualties were suffered as a result of any persistent radioactivity of
fission products of the bomb, or any induced radioactivity of objects near
the explosion. The gamma radiations emitted by the nuclear explosion did
not, of course, inflict any damage on structures.