Google and Microsoft have introduced software that makes it harder for users to search for child abuse material online, the companies said in a joint announcement.
Writing ahead of a British summit on Internet safety, Google's executive chairman Eric Schmidt said his company has fine-tuned Google Search to clean up results for over 100,000 search terms. When users type in queries that may be related to child sexual abuse, they will find no results that link to illegal content.
"We will soon roll out these changes in more than 150 languages, so the impact will be truly global," Schmidt wrote in the Daily Mail newspaper.
The restrictions are being launched in Britain and other English-speaking countries first. Similar changes are being brought out on Microsoft's Bing search engine.
The two companies are sharing picture detection technology to identify child abuse photographs whenever they appear on their systems, and Google is also testing technology to identify and remove illegal videos.