Panic is a term used loosely to describe a variety of such social situations in which a portion of the population responds irrationally to socio-economic, military, or other crises, whether real or anticipated or imaginary. Epidemic or mass hysteria is said to explain a variety of irrational or bizarre behaviour affecting persons in close proximity to each other. Concern on the part of authorities at the possibility of causing mass panic is frequently cited as a reason for suppressing information concerning potential hazards.
Panic may follow acute financial crises, widespread bank failures, stock market failure, or the threat of attack. In the case of chemical and biological warfare, for example, it may cause individuals to flee from the area, even when there is no longer any danger of exposure, thus making it almost impossible either to bring personnel or material into the affected area to help cope with the casualties or to evacuate those affected.