The Animal Liberation Front (ALF) is an international, leaderless, decentralized political and social resistance movement that advocates and engages in what it calls non-violent direct action in protest against incidents of animal cruelty. It originated in the 1970s from the Bands of Mercy. Participants state it is a modern-day Underground Railroad, removing animals from laboratories and farms, destroying facilities, arranging safe houses, veterinary care and operating sanctuaries where the animals subsequently live. Critics have labelled them as eco-terrorists.Active in over 40 countries, ALF cells operate clandestinely, consisting of small groups of friends and sometimes just one person, which makes internal movements difficult for the authorities to monitor. Robin Webb of the Animal Liberation Press Office has said: "That is why the ALF cannot be smashed, it cannot be effectively infiltrated, it cannot be stopped. You, each and every one of you: you are the ALF."Activists say the movement is non-violent. According to the ALF's code, any act that furthers the cause of animal liberation, where all reasonable precautions are taken not to harm human or non-human life, may be claimed as an ALF action, including acts of vandalism causing economic damage. American activist Rod Coronado said in 2006: "One thing that I know that separates us from the people we are constantly accused of being—that is, terrorists, violent criminals—is the fact that we have harmed no one."There has nevertheless been widespread criticism that ALF spokespersons and activists have either failed to condemn acts of violence or have themselves engaged in it, either in the name of the ALF or under another banner. The criticism has been accompanied by dissent within the animal rights movement itself about the use of violence, and increasing attention from the police and intelligence communities. In 2002, the Southern Poverty Law Center (SPLC), which monitors extremism in the United States, noted the involvement of the ALF in the Stop Huntingdon Animal Cruelty campaign, which SPLC identified as using terrorist tactics—though a later SPLC report also noted that they have not killed anyone. In 2005, the ALF was included in a United States Department of Homeland Security planning document listing a number of domestic terrorist threats on which the U.S. government expected to focus resources. That same year FBI deputy assistant director John Lewis stated that "eco terrorism" and the "animal rights movement" were "the number one domestic terrorism threat." In the UK, ALF actions are regarded as examples of domestic extremism, and are handled by the National Extremism Tactical Coordination Unit, set up in 2004 to monitor ALF and other illegal animal rights activity.