The number of web pages found with images of child sexual abuse soared by 137% last year, a UK internet watchdog has revealed.
The Internet Watch Foundation (IWF) said it removed 31,266 URLs hosting pictures and videos of children being sexually abused in 2014, compared with 13,182 in 2013.
It comes after the regulator was given new powers to seek out criminal content online in the wake of the murders of Tia Sharp and April Jones.
Both girls were murdered by men who had previously viewed child sexual abuse images on the internet.
IWF chief executive Susie Hargreaves that while the online industry was “stepping up” efforts to tackle child sexual abuse images, many companies did not recognise they had a problem, or were too slow to respond.
“It is not good enough for those companies to allow the burden of responsibility to fall on a socially responsible few,” she said.
“This year will ensure they have nowhere to hide as we will be targeting them for the benefit of all internet users and victims of sexual abuse.”
The IWF, which was launched in 1996, is funded by 117 companies and organisations including technology giants Apple, Google, Facebook and Twitter.
An increase in funding last year saw the watchdog recruit another eight internet content analysts to root out child abuse imagery online, taking their total to 12.
In its annual report for 2014, the IWF said 0.3% of imagery found last year was hosted in the UK, compared with 18% in 1996. Most of the images identified were hosted in North America (56%).
Ninety five UK-based web pages or URLs were removed in 2014 because they were hosting child sexual abuse images and videos, the IWF said.
Around 89% of those pages contained images of children aged 10 or under, an increase from 65% in 2013 and 79% in 2012, the watchdog added.
Emma Hardy, the IWF’s director of external relations, said: “The biggest change for us last year was our ability to proactively search for child sexual abuse imagery.
“Our analysts are able to actively search for the content, rather than merely wait for reports to come in from the public.
“That’s made a huge difference. Last year we were able to process 74,000 reports and within that we were able to identify just over 31,000 child sexual abuse web pages.
“I think there’s still a huge amount out there. We’ve got a long way to go until we see the peak of this problem.”
The IWF found many legitimate online services were being abused by criminals distributing child sexual abuse imagery.
Image hosting services, where users can upload images and make them available via a unique URL, were most abused last year, the IWF said.
The number of image-hosting URLs removed rose from from 5,594 in 2013 to 19,710 in 2014.
Meanwhile, cyberlockers – which are online file hosting services, cloud storage services or online file storage providers – saw 5,582 URLs removed because they were hosting child sex abuse images in 2014 compared with 1,400 in 2013.
The IWF said it alerts law enforcement agencies and hotlines in other countries when it discovers foreign-based web pages with child sexual abuse images and “repeatedly chases” them until they are removed.
Writing in the report. Home Secretary Theresa May said: “The IWF plays a vital role in combating child sexual abuse and protecting children from these despicable crimes.
“Its introduction of proactive searching across the internet has vastly increased the number of abuse images being removed from circulation.”