Use or create a catastrophical event

Schneier in "Beyond Fear" describes a bank robbery. A volcano erupted, covering a nearby city with ash. City got evacuated, then completely buried under ash. Shortly afterwards the enterpreneurs came, dug a hole through the ash into the bank, and removed the money.

For gaining access to data or materials in a facility, a catastrophical event can be exploited (e.g. a flood) or staged (a fire). Data recovery from flooded or fire-damaged disk drives is commercially available. Access to a freshly burned-down or flooded facility may be made easier by the damage done to the security system, and the overall chaos of the situation.