Eco-terrorism is an act of violence which is committed in support of environmental causes, against people or property. The United States Federal Bureau of Investigation (FBI) defines eco-terrorism as "...the use or threatened use of violence of a criminal nature against the people guilty of destroying the environment or their property by an environmentally-oriented, subnational group for environmental-political reasons, or aimed at an audience beyond the target, often of a symbolic nature." The FBI credited eco-terrorists with US $200 million in property damage between 2003 and 2008. A majority of states in the US have introduced laws aimed at penalizing eco-terrorism.