The children, who are all in care, were allegedly taken to a hotel in Birmingham by a man they knew and pressured into sexual activity as others watched.
A string of abuses including sex acts with a rabbit, dog and other animals were reported to authorities by child welfare social workers caring for the alleged victims.
No one was identified in a written ruling but it is believed that all the sex acts were captured on video.
Following a family court hearing at Coventry Crown Court on Thursday, Judge Hilary Watson analyzed the evidence and made a series of findings.
Judge Watson said the local authority with responsibility for the children was Coventry City Council. She said that police were involved, but she failed to reveal whether anyone has been charged.
Further commenting on the case, Watson said some of the allegations may seem “fantastical.” However, she concluded they were likely to reflect the “grim reality” of what the youngsters were subjected to.
“In my judgment, the children are telling the truth when they describe being taken … to a hotel where they had wine and tablets and were made to perform sexual acts watched by other people,” she said.
“It is suggested that the accounts are not to be believed because the children report sexual activity with [a] dog and other animals. A rabbit was described as being frightened … and running off.
“Such suggestions might seem fantastical but become a grim reality when seen in the context of my findings that the children have been made to perform sexual activities with each other for the sexual gratification of [the man], for the video camera, and for other people.”
The judge added: “It is highly probable that the children were made to perform sexual acts on animals.”
The suspect at the heart of the child sex abuse scandal has denied threatening or harming the children.
When speaking about the accused, Judge Watson insisted that the man “threatened them [the children] with violence.”
"[He] has orchestrated sexual activity between children for his personal sexual gratification,” she said.
‘Child sex abuse woven into British society’
The judge’s findings will be used in ongoing proceedings to decide the future of the alleged victims.
There are currently over 50,000 children identified as needing protection from abuse in the UK, according to the National Society for the Prevention of Cruelty to Children (NSPCC).
One in 20 children in the UK have been sexually abused and one in three are too frightened to report the incidents to police. Experts believe over 90 percent of sexually abused children were abused by someone they knew.
In March last year, Home Secretary Theresa May warned that child sex abuse is “woven, covertly, into the fabric” of British society.
Writing in the Daily Telegraph, she said the public was yet to grasp the full scale of the problem.