China's widely criticised blocking of the web's most popular search engine Google can be defeated by viewing a strange Google mirror site through a mirror, New Scientist has discovered.

The mirror site, called elgooG, is a parody of the English language version of Google in which all the text on the web pages has been reversed. The text terms used for searches are also entered in reverse. The site, which returns all the same hits as Google, can be accessed from behind China's "great firewall".

Viewing the page using a mirror makes it somewhat easier to read, and would allow someone to find a website. Web site "mirroring" normally involves copying the contents of a site and hosting on a different server. This can be useful if one server is particularly busy.

New Scientist ascertained that elgooG is accessible from China using a system that remotely tests China's internet restrictions. The system was created by two researchers at the Berkman Center for Internet & Society at Harvard Law School in the US.

Routine block

Google has been blocked inside China since at least 1 September. It emerged on Friday that a second search engine Altavista is also restricted. The action has come under criticism from western human rights groups and journalist's organisations.

China's government routinely blocks access to news sites that host content they consider unacceptable, such as the BBC's news site. Web proxies including anonymizer.com and safeweb.com, which can be used to view pages on one site through another, are also blocked.

The reason for the latest restrictions is not clear but observers have speculated that government elections in November could have prompted a crack down on access to information via the internet.

Content cache

Google could have been targeted because it provides a cache of content from other web sites that are already under government blackout. However, Altavista does not.

The country's 45 million internet users can only access the web through government-run ISPs. This means that any site can be blocked easily.

The company behind Google has released programming information that provides remote access to its search capabilities. This means mirror sites can be created without having to duplicate Google's colossal database, though to date New Scientist has only identified elgooG.

If you would like to reuse any content from New Scientist, either in print or online, please contact the syndication department first for permission. New Scientist does not own rights to photos, but there are a variety of licensing options available for use of articles and graphics we own the copyright to.