Eco-terrorism usually refers to acts of violence or sabotage committed in support of ecological or environmental,against persons or their property.
Eco-terrorism is defined by the Federal Bureau of Investigation as "the use or threatened use of violence of a criminal nature against people or 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 has credited to eco-terrorism 300 million dollars in property damage from 2003 and 2008, and a majority of states within the USA have introduced laws aimed at these activities.
Critics of this use of the term argue that it has been defined in order to vilify activists, and that the term would be more properly employed to describe the environmentally damaging activities of corporations.
Read more about Eco-terrorism: Application of The Term, Examples of Tactics, Groups Accused of Eco-terrorism, Philosophy of Eco-terrorism, Government Response in The USA