( CNN ) -- A surprise appearance by WikiLeaks.org founder Julian Assange at the TED Global conference in Oxford , England , has cast new light on the activities of the site and its mysterious leader . Assange 's site , which released video of a U.S. air strike in Iraq that killed a dozen civilians , claims to have revealed more classified intelligence documents than the rest of the world 's media combined . Explaining during his appearance Friday why WikiLeaks has been keeping a lower profile since releasing the video , Assange said it was working on raising funds and strengthening its technical infrastructure to handle more traffic while accumulating `` an enormous quantity of whistle-blower disclosures . '' He later told reporters that `` there are many things which are very explosive . '' Assange , 39 , said the site operates from several countries , including Sweden and Belgium , where laws provide more protection for its disclosures . He said he canceled plans to travel to the United States for three public appearances , citing what he described as indications that U.S. officials might not follow the `` rule of law '' in dealing with him . He also mentioned advice from investigative journalist Seymour Hersh to be cautious . He said U.S. officials have since adopted a more `` reasonable '' stance . TED Global is an annual conference hosted by the nonprofit organization TED , named after the three subjects it first began discussing in the 1980s : technology , entertainment and design . It has expanded its scope in the years since and its website now hosts more than 700 talks on a wide range of topics . Learn more about speakers at the TED Global conference . In an onstage discussion with TED curator Chris Anderson , Assange was asked whether is was true he had attended 37 schools as a child . He explained it was a consequence of two things : his parents were in the movie business and were later `` on the run from a cult . '' Assange said he became a `` journalist activist '' in his teenage years and was prosecuted for it . According to political magazine Mother Jones : `` As a teenager in Melbourne , he belonged to a hacker collective called the International Subversives . He eventually pled guilty to 24 counts of breaking into Australian government and commercial websites to test their security gaps , but was released on bond for good behavior . '' Asked about his core values , Assange said , `` Capable , generous men do not create victims , they nurture victims , '' attributing the thought to his father and others . `` I 'm a combative person , so I 'm not actually so big on the nurture , but there is another way of nurturing victims , which is to police perpetrators of crimes . And so that is something that has been in my character for a long time . '' Read more about Assange and his site . Assange said the organization gets material from whistle-blowers in a variety of ways -- including postal mail . He said WikiLeaks vets it , releases it to the public and then defends itself against `` political or legal attack . '' He said the organization rarely knows the identity of the source of the leak . `` If we find out at some stage , we destroy that information as soon as possible , '' he said . Pfc . Bradley E. Manning , 22 , of Potomac , Maryland , has been charged with eight violations of the U.S. Criminal Code for allegedly illegally transferring classified data , including the video that wound up on WikiLeaks . He has been accused of `` wrongfully introducing a classified video of a military operation filmed at or near Baghdad , Iraq '' around July 12 , 2007 , `` onto his personal computer , a nonsecure information system . '' Watch the video of the airstrike . Assange said at a news conference after his appearance Friday that Manning `` is a political prisoner being held in the nation of Kuwait , effectively keeping him away from the press and effective legal representation . '' He said WikiLeaks is providing legal assistance to Manning without saying whether he was the source of the video . `` Obviously , we can not pick and choose , '' said Assange , adding the site has to defend everyone who faces serious charges as a result of material posted on WikiLeaks . The video shows aerial footage of an attack by a U.S. Apache helicopter that killed civilians , including two journalists from the Reuters news service . WikiLeaks posted it in April . The site said the video `` clearly shows the unprovoked slaying of a wounded Reuters employee and his rescuers . '' Asked to respond to Assange 's assertion that Manning is a political prisoner , Pentagon spokesman Col. David Lapan told CNN last week that Manning is `` accused of committing serious offenses . He has been charged under the Uniform Code of Military Justice and will be processed by normal procedures through the military justice system . '' U.S. military authorities have warned that the publication of classified documents on WikiLeaks could aid in the planning of terrorist attacks and harm national security . Assange denied reports that WikiLeaks had received hundreds of thousands of classified U.S. cables in addition to the Iraq video . He said the site would have released the cables if it had received them . Some information , such as private medical records , should be kept secret , Assange said , but he did not extend that view to classified documents . The fact that governments spend money to keep such information secret , Assange said , is a good indication that releasing the information can achieve reform . Anderson asked the audience for a show of hands as to whether he was a hero or a dangerous troublemaker . The vast majority signaled that they viewed him as a hero . CNN 's Mike Mount and Alan Silverleib contributed to this report .
WikiLeaks.org WikiLeaks publishes documents of political or historical importance that are censored or otherwise suppressed. He says the site has been overwhelmed by disclosures from whistle-blowers . Assange said site has disclosed more classified documents than rest of world 's media combined . He said WikiLeaks will defend Army private accused of leaks but site wo n't name source .