A paedophile has admitted raping a 14-month-old baby girl and filming the abuse on a webcam at his home.
David Morrison, 45, of Grangemouth, also admitted being in possession of a library of child abuse images at the High Court in Glasgow on Friday.
Morrison admitted that he raped the child after evidence of the sexual abuse was built up by police through combining online chat logs, photographs and expert analysis of veins in Morrison's hands.
He also admitted taking, possessing and distributing images through the internet.
The investigation found he stated online that he intended to carry out the act. Detectives who seized his computers then discovered he had taken a video clip of the rape, sent the image to a paedophile in the USA and then spoke about it online afterwards.
Detective Inspector Barry Blair, of the Public Protection Unit, which led Operation Malta, said: "This man is undoubtedly one of the most dangerous sexual predators we have ever investigated. We know that children in the Forth Valley area and beyond are considerably safer now he has been convicted at court of these despicable offences.
"A comprehensive and unique evidential jigsaw helped us to charge Morrison with rape, to which has now pleaded guilty. We were able to piece together his offending by examining his chat logs to other offenders immediately before the offence took place, detailed examination of the images he had taken of the abuse actually taking place and looking at chat logs immediately after the offence had taken place.
"Experts were able to tell us, that by examining the patterns of veins on the back of a hand in one of the images and comparing that with photos we took of Morrison's hands, the person in the photo was him. They were also able to tell us by closely scrutinising the backgrounds of the images that the photos were taken in his home."
Expert analysts were able to identify the location in the image as his home and that a hand which featured in the photograph was that of Morrison.
The pattern of veins on the back of his hand was compared to Morrison’s, confirming that he had committed the act.
Forensic examination of five hard-drives taken from his home revealed Morrison had been in contact with paedophiles in 25 countries. In the UK alone, 15 people have been arrested as a result of the inquiry. Three children were removed from harm after being identified as at risk.
In total Morrison was found with more than 13,000 downloaded and uploaded images, including photographs and videos.
A number of the child abuse images found in the investigation that began in December 2010 were of the most severe kind.
More than 30 police officers and staff worked on the investigation, alongside representatives of other agencies.
Detective Sergeant Douglas Howie, of the Specialist Investigations Unit, which investigates online crime and sexual abuse, said: "The possession and distribution of child abuse images is in no way a victimless crime. Morrison was in contact with more than 200 people around the world through the internet, who were all like-minded individuals who were interested in the sexual abuse of young children. In the UK alone, three children were effectively rescued from being at risk.
"Morrison was carrying out sex abuse on a small child and posting those images around the world for the gratification of others. I cannot think of a more abhorrent offence."
Anne Donaldson, Central Scotland Procurator Fiscal, added: "David Morrison has today pled guilty to offences that any civilised person will find it impossible to comprehend.
"He sexually abused a child and transmitted images of this abuse via a webcam. He made and downloaded indecent images of children and shared these photographs on the internet. "Working closely with police specialists, who utilised the latest technology to uncover the extent of his offending, the expert prosecutors in our National Sexual Crimes Unit have today brought Morrison to justice for these most despicable of crimes.
"I want to reassure the public that the prosecution service will work tirelessly to ensure that there is no place to hide for those intent on committing child abuse. They will be found, and they will be brought to justice."