A gang of "evil" paedophiles who raped babies, toddlers and pre-school children in abuse that was streamed over the internet have been jailed.
The men, described as "beyond human instinct", preyed on the families of youngsters to gain access to them, in once case grooming a mother and father before their baby's birth.
Members travelled hundreds of miles to carry out attacks together, or used internet streaming to provide real-time encouragement and directions to those abusing victims.
Chat logs revealed the gang would offer advice on using "date rape" drugs or over-the-counter medication to drowse children and babies.
The seven men, aged between 31 and 51, were convicted of 29 child sex abuse offences, including the multiple rape of an 11-month-old baby.
They are John Denham, 50, from Wiltshire, Matthew Stansfield, 35, from Hampshire, Adam Toms, 33, from Somerset, Christopher Knight, 35, from Manchester, Robin Hollyson, 31, from Bedfordshire, David Harsley, 51, from Yorkshire, and Matthew Lisk, 33, from Sussex.
Judge Julian Lambert jailed the men, including two who are HIV positive, to terms ranging from two to 24 years and ordered all but one to register as sex offenders for life.
"In the worst nightmare, from the very deepest recesses of the mind, at the darkest hour of the night, few can have imagined the terrifying depravity which you men admit," the judge said at Bristol Crown Court.
"What you contemplated and what you did involved the most horrific abuse of a baby and very young children.
"Your thoughts and deeds are beyond human instinct and reason, and are evil beyond rational understanding."
He said the men had sought out the "darkest materials on the internet" and planned "the most shockingly sordid exploitation of the very young".
The National Crime Agency launched an investigation last September after Toms admitted to police that he had abused a child.
He provided the details of 40 others involved and officers began the painstaking process of gathering evidence from fragments of deleted files and chat room logs.
Three victims - a baby and two four-year-old boys who live in different parts in the country - were identified, while 30 other children were safeguarded.
Further prosecutions are expected.
Members used Skype, video conferencing software and the "dark web" to coordinate and view the attacks.
Up to 25 men joined each session, which included watching a 17-year-old boy abuse his four-year-old brother in America.
Hollyson gained "access" - a phrase used by the men - to a baby in 2013 and boasted of repeatedly raping the boy from the age of three months.
He filmed himself doing so between December 2013 and January 2014.
In May 2014, Hollyson, Stansfield and Toms took turns to rape and sexually assault the baby while sharing footage online.
Video clips from July 2014 show Hollyson further abusing the boy.
The infant was posed in photographs advertising the chat room where his abuse would be streamed.
In April 2014, Toms administered drugs to a four-year-old boy so he and Knight could abuse him, with photographs of the incident shared online.
Many of the defendants also possessed some of the worst child images imaginable, Judge Lambert said.
Hollyson was jailed for 24 years, Toms for 12, Knight for 18, Stansfield for 10, Denham for eight, Lisk for four and Harsley for two years.
All but Harsley were handed extended sentences and placed on the sex offenders' register for life.
One of the victim's families said: "No family ever wants to find that their child has been the victim of abuse, nor would they ever knowingly put their child at risk."