POLICE have welcomed a bid to remove millions of images of child abuse from the net - but warned against "complacency" in the fight against paedophiles.

Web giants Google, Facebook and Twitter have joined forces with British charity Internet Watch Foundation (IWF) as part of a crackdown on indecent images.

The move - a UK first - will see the anti-abuse organisation sharing lists of such images, identified by unique 'hash codes', with the international internet companies.

Wider use of the photo-tagging system could be a "game changer" in the fight against paedophiles, bosses at IWF believe.

The charity was launched with the aim of removing indecent images of children from the internet, allocating to each a unique 'hash'.

By sharing 'hash lists' of the photographs, Google, Facebook and Twitter will be able to stop the images from being uploaded to their sites.

Detective Sergeant Mark Fursman, of Dorset Police’s Paedophile On-line Investigation Team (POLIT), said: “The policing of the internet requires the help and support of businesses as well as law enforcement and internet organisations to combat children being sexually exploited for sexual gratification.

"POLIT works with the Internet Watch Foundation and law enforcement agencies nationally and internationally and welcomes any developments to ensure children are safeguarded from abuse.”

Dorset's Police and Crime Commissioner Martyn Underhill said: "Every indecent image online has a vulnerable victim behind it, so any initiative to block them being posted online is fantastic."

However, he warned: "We can't be complacent."

"The current trend for these images, and for most other types of cyber crime, is the move into the dark web, which is very hard to currently police," he added.

"As the IWF shuts down online social media to paedophiles, that's where our challenge now lies."

The 'dark net' is a network with restricted access that can only be accessed with specific software or authorisation.

It includes material on the internet that a search engine cannot access and has been intentionally hidden and is inaccessible through standard web browsers.

Software such as Tor enables users to access the dark web to email and host file storage through encrypted and anonymised networks.