[syriacus]

and how does anyone know what is in the barrels. Might just be good old sand put there to fool the inspectors.

Exactly. The same trucks that took the explosives away might have brought sand.

[cookcounty]

The FedEx hazmat guy (FedEx does more hazmat shipments than any other company in the world) says:

The IATA UN classification number for HMX in 0226. This should appear as UN 0226 in bold black lettering enclosed by a black rectangle, and must be on two opposing sides of the container.

The"23----" that appears on the barrel near the IATA sticker may be a sloppy rendition of a UN number improperly executed. If so, this is not HMX.