A British man living in the US has pleaded guilty to plotting to kidnap a child as well as possessing and distributing child pornography.
Authorities also said 40-year-old Geoffrey Portway had a dungeon in his home in Worcester, Massachusetts and spoke of his desire to abduct, kill and eat children.
Portway was arrested in July after police allegedly found child pornography and photos of children who appeared to be dead on his computer.
According to the agreed statement of facts released by Boston officials, Portway also had numerous chats online with people to discuss a "mutual interest in abducting, raping, murdering, and eating children".
Portway has been sentenced to between 18 to 27 years in prison and will be deported back to the UK following his release. He will also be made to sign as a Level 3 sex offender.
When police searched Portway's home following his arrest, they discovered a dungeon in the basement.
According to police, the dungeon contained a child-sized homemade coffin with large speakers covered in wire mesh at one end, as well as a steel cage approximately 3 feet wide, 2 feet high and 4 feet long, and a steel table top.
Police also recovered a number of disposable scalpels, butchering kits and castration tools from the 40-year-old's home.
The dungeon was intended for kidnapped children to be abused and killed, according to the US attorney.
The statement added: "This dungeon was described in detail by Portway in recovered (online) chats as a place he intended to use to keep kidnapped children while he sexually abused them and as a place to eventually murder and cannibalise the children.
"Many of these conversations were accompanied by the trading of child pornography. These chats also included images of children known to them, accompanied by discussions of the desire to sexually abuse, murder and cannibalise those children."
One of the people with whom Portway conspired to kill and eat children was Kansas resident Michael Arnett. Court filings state Portway used Skype and other programs to communicate with Arnett and to trade child pornography, including images of injured, mutilated and deceased children.
Arnett agreed that he would eventually kidnap a child for Portway, who would then rape, kill and eat that child.
Arnett has pleaded guilty in Kansas to the sexual exploitation of a child to produce pornography.
Both men were arrested as part of an ongoing investigation which started in 2010. The operation has since expanded to Europe and other countries.
Bruce Foucart, special agent in charge of Homeland Security Investigations in Boston, said: "Thanks to the determination of HSI, along with our partners at the U.S. attorney's office, we have been able to rescue 160 children and arrest 51 perpetrators worldwide."