The photo below shows two shots facing roughtly north on West Broadway, in the block just north of Barclay St, after both Twin Towers collapsed, but before the collapse of WTC 7. Strangely, the cars were incinerated but the nearby buildings, even closer to Ground Zero, seem to be unaffected, as is the office paper that floated down to street level after the impacts. We have seen no reports of the fuel tanks exploding.
Note the following in the composite photo below:

The various types of insult to these cars may indicate a plurality of damage modes, and suggested options range from novel star wars beam weapons proposed by Judy Wood and Morgan Reynolds to a wave of EMP that instantaneously heated the cars' metal to red hot with induced electrical currents. Dr. Stephen E. Jones explanation seems to fit many of them, however: that the excess oxidative capacity of hot thermate cutter-charge material raining down from the collapses, hidden by the pyroclastic dust clouds, fell on the cars and oxidized them (page 75).
Since no official investigation questioned why these cars burned, its determination remains an action item for independent efforts.
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