Police forces across four continents raided the homes of 130 suspects throughout the night in the biggest ever international operation against Internet paedophiles.

Nineteen countries were involved in the operation, which resulted in the execution of 130 search warrants throughout the night. The dawn swoops are reported to have discovered 60,000 images of child pornography. The investigation, dubbed Operation Landmark, successfully identified 12 suspected paedophiles in the United Kingdom. At 10 pm PST Tuesday, the National Crime Squad (NCS) coordinated dawn raids on the 12 British targets; computers and software were seized as evidence.

The NCS confirmed that it will use sophisticated face-mapping software to identify the children depicted in 60,000 pornographic images obtained through the raids. A source close to the international investigation said the new software is designed to help trace the whereabouts of the victims and their abusers.

Detective Superintendent Peter Spindler, leading the investigation for the NCS, said, "This operation has sadly and distressingly brought thousands of new images of abuse to our attention. These young victims need to be identified and protected as quickly as possible."

Information technology company Serco Group was commissioned to develop the face-recognition software for the NCS following Operation Cathedral--an international operation that led to the arrest and imprisonment of the world's largest Internet paedophile ring, the Wonderland Club. All information gathered using the new software will be entered into an international police database.

"We hope that the database can be used to identify children who are being systematically abused for the gratification of a small but dangerous section of society," Spindler said.

A combination of existing software has been used to develop the face-mapping tool and has been designed according to the NCS and Interpol specifications.

"Until now, most of the face-recognition that has been done on file images has only worked if the picture is exact," a source said. "A number of police databases already contain hashes of known paedophile images, but the moment the picture becomes cropped, it no longer works."

The new software will allow officers at the NCS and the National Hi-Tech Crime Unit (NHTCU) to identify abused children who may look slightly different from one picture to another. It will also provide intelligence on the background in the photos, which could be used to determine the room in which the photos were taken and then linked to the abuser or photographer.

"This is an experimental exercise--I'm not sure how effective the software is," the source said.

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