New York, Aug 11 (IANS): Silicon Valley giants Facebook, Google, Microsoft, Yahoo and Twitter are working with Britain's Internet Watch Foundation (IWF) to implement a new system that will help detect and block images of child pornography online.

IWF, a charitable foundation, has introduced a new technology that enables it to tag images of sexual abuse with distinct hashes -- sort of codes that act like a digital fingerprint, The Verge reported.

Once a hash is assigned to an image, it's unique to it, making it easy to identify a specific image.

The IWF keeps a record of all the hashes, which it has only shared with the five tech companies so far, but plans to roll out to others soon.

Once the system is implemented, any image that is uploaded to Facebook, Twitter or any other participating website is scanned.

If the image has previously been tagged by the IWF, the system will detect its hash and automatically prevent it from being uploaded -- and thus from being shared.

Google has long scanned the images that pass through Gmail for child pornography. Now, the joint support of the tech giants should help widen the net.