Circa 1989-1990. I recall reading a wire report (either AP or UPI) in
one of the Atlanta daily papers about a banking check scam. The con
artist(s) would present the teller with a check and proceed to
withdraw sizeable amounts of money from an account. Minutes later,
before the check could be processed by the bank, it would apparently
disintegrate, leaving behind just ashy residue. IIRC, the ink used on
the checks was purple and there was something about a banana odor.

Were the bank robbers ever caught? 

Is there some explanation as to how the checks disintegrated?

How widespread was this crime?

Was this the brainchild of Frank Abagnale, Jr.?

Abagnale had stopped working as a con man long before '89/90. He had
started a company that specialized in working with banks to protect
against cons/counterfeiting by then so I doubt that a scam like this
had anything to do with him. This also sounds a bit like an urban
legend.

forge

Forge. I know it sounds incredible but I do not believe it is an urban
legend. However I would hate to have believed this was a true bank
scam story all these years and it turns out it's not.

Thanks for writing.