The BBC has launched a Tor-based version of its news website, to help circumvent state efforts to censor the free flow of information around the world.

Countries such as Russia, China, Iran and Vietnam have tightened efforts over recent years to monitor and control what their citizens can access online.

However, Tor, short for The Onion Router, offers an anonymous way for individuals and business users to bypass such controls. Developed by the US Navy in the 1990s, it routes data in highly complex patterns across the internet via “nodes” hosted by volunteers.

Encryption is applied at each layer to maintain user anonymity, with any website receiving a request tricked into believing the exit node is the user’s location.

As well as enabling users to visit regular websites anonymously, Tor allows sites to be hosted at addresses on the non-index, or dark web, via a .onion address. Perhaps the biggest benefit of this is that .onion addresses won’t work unless accessed via a Tor browser, so it means users can’t accidentally not use Tor when browsing for them.

“The BBC World Service’s news content is now available on the Tor network to audiences who live in countries where BBC News is being blocked or restricted,” the BBC said in a statement. “This is in line with the BBC World Service mission to provide trusted news around the world.”

Foreign language services including BBC Arabic, BBC Persian and BBC Russian will be available via the new service, hinting at some of the regions that are affected most by state-level censorship.

The announcement highlights the benefits of the dark web to many users around the world, including rights activists, journalists and ordinary citizens who may otherwise be persecuted by authoritative regimes.

It’s a counterpoint to most news about such sites, which focus on the dark web marketplaces for drugs, weapons and other illegal goods.