Tales to Astonish #60 Oct 1964
"The Incredible Hulk!"
Bruce creates an indestructible robot which is able to withstand the power of a nuclear blast
but the stress of completing it on schedule causes him to transform into the Hulk
and he leaves this massive weapon of awesome power unattended;
So of course, a foreign spy who has been hanging around gamma base
looking for just such an opportunity jumps into the robot and takes off.
Script by Stan Lee,
art by Steve Ditko and George Roussos (as George Bell).