It is a crowd phenomenon that occurs when the police cannot control people.
In such an incident, security is very lax, largely because law enforcement are busy dealing with the actual problem. The collapse of infrastructure also makes it hard to protect property.
Looters see the disaster as an opportunity to better themselves without the risk of being caught. This may because a large number of other people are also looting, the fact that the property loss may be attributed to the actual disaster, and the feeling that other people will loot it eventually anyway.
Looters may have often lost a lot of their own property, and see looting as a chance to benefit out of a bad situation. This is usually the case as looters rarely come from another unaffected location to steal.
Following the death of Valentinian III in 454, the Vandals invade Rome, extensively looting it.
During the terrorist attacks of September 11, 2001 many ATMss were robbed in New York.
After the United States occupied Iraq, the absence of Iraqi police, and the reluctance of the US to help enabled looters to raid homes and businesses. During the war, hospitals were stripped of nearly all supplies.Looting in the world
Without a police presence, looting will nearly always occur in large scale disaster situations.