The number of internet child pornography sites reported to police soared by almost 80% last year, according to a new report.
IWF urges the public to report potentially illegal sites
The Internet Watch foundation (IWF) said 6,128 sites investigated after reports to them from the public were illegal - up from 3,438 in 2004.
The 78% rise compared to an increase of 0.003% in the previous 12 months.
The increase was due to public intolerance of child abuse and better tracking of sites, the IWF said.
The organisation's annual report said 23,658 reports of suspicious content were sent to the IWF by members of the public with 6,128 then passed on to the police.
It found that just 0.4% of child abuse content was hosted on UK-based websites.
Some 40% of child internet pornography was traced to the US, 28% to Russia, 17% to Asia and 13% to mainland Europe.
Chief executive Peter Robbins said agencies dealing with internet child pornography needed to accept that pay-per-view websites providing "criminal content" were "forever on the move".
"This is big business. These sites hop around from country to country and it's clearly very lucrative," he told BBC News.
"If we pass on information to the Russian authorities or the US authorities and, when they go to look up the website its not there, they don't take any more action because its not in their backyard."
The IWF is now working with agencies in other countries to teach its methods abroad.
The NSPCC praised the IWF for getting across the message that internet crime was everyone's responsibility.