A former teacher has given a damning indictment of behaviour at a £30,000-a-year public school, claiming that a pupil skinned live cats, stoned wild birds and wrapped a younger boy in clingfilm and duct tape before beating him with belts.
And she claimed that when she told the headmaster about the incidents, she was told: "Boys will be boys."
The astonishing allegations were made by Rachel Ashley, a former housemistress at Oratory School in Oxfordshire – the UK's only independent all-boys Catholic school – at a tribunal.
She is suing the school for constructive unfair dismissal and public interest disclosure at an employment tribunal.
Mrs Ashley told the tribunal in Reading that she eventually left The Oratory after one of the boys she complained about was allowed to return to lessons after holidays, despite her whistle-blowing.
Mrs Ashley said a 15-year-old boy, who was identified only as Boy A for legal reasons, had made a large fire on a trip to Edinburgh using lighter fuel, before making flame throwers out of spray paint canisters.
She said in a statement: "Boy A also manufactured weapons in his [school] room – garrottes from heavy scavenged chain and nailed gloves. He also had a five-foot tungsten bow and arrows which were illegally purchased.
"He also had a hi-tech BB gun; he filmed himself skinning live cats and trapped and pounded to death large birds."
Mrs Ashley, who began working at The Oratory in September 2009, said she had raised her concerns with Dr Tony Stroker, housemaster at its Faber House, and deputy headteacher and child protection officer, Tom Hennessey. The weapons were then confiscated.
She said: "Tom told me regularly 'there is only so much I can do'.The headmaster's view was 'boys will be boys' even in relation to the most appalling behaviour."
Despite two psychiatrists deeming Boy A to be 'of grave concern', Mrs Ashley said she was told he would be allowed to return to the school after the summer holidays, which she said would mean she had to leave.
She said: "I felt he was so dangerous to me and the pupils that his return would cause me a real problem."
Around the middle of August, it was decided that Boy A would not be returning to the school and Mrs Ashley was informed of this.
Mrs Ashley, from Finchampstead, Berkshire, also claimed that a younger boy identified as Boy B was attacked by other boys all aged 18 or 19 years, on his way to the lavatory.
She said he was dragged out onto the school's cricket pitch and bound with cling film and duct tape before being beaten with shoes and a belt, causing bruising.
Mrs Ashley said Mr Hennessey told her 'we were lucky not to have found him swinging' as the boy was so traumatised by the attack.
He asked the headmaster that his parents not be told, this was granted and within a few days, Boy B flew home, she said. Just three days later, one of his attackers was awarded a prize in an awards ceremony.
One of the boys who attacked Boy B allegedly told Mrs Ashley: "It was much worse than you think, we wanted to kill him."
She said this incident was the final straw and she handed in her notice on September 5 and submitted a whistle-blowing letter detailing the incidents and alleged mishandling and cover-ups by the school.
The tribunal heard from Alison Beasley, a safeguarding officer from Oxfordshire County Council, conducted an investigation into the attack on Boy B.
She said: "I did not find evidence that there had been a collusion by the school to cover-up criminal offences and did not uphold this aspect of the complaint.
"The school had actively sought medical attention and liaised with the health professionals, as well as instigating an internal investigation.
"The fact Boy B and the pupils involved had left the school meant there was no continuing risk of harm to him. This, and his requests for no action to be taken, would probably have meant no further action would have been taken if the matter had been referred to us."
The hearing continues.