Axel Rudakubana's father has said he is "desperately sorry" for failing to challenge his son's violent behaviour over the years before the Southport attack.
Alphonse Rudakubana told a public inquiry he was "frightened" of his son, who once poured a bottle of oil over him and said: "Trust me, I will kill you."
He said Axel's behaviour deteriorated in a "short period of time" until he was expelled from the Range High School in Formby, Merseyside, in October 2019 after admitting to carrying knives.
Two months later, he returned to attack a pupil with a hockey stick, while armed with a knife and was arrested and made subject to a referral order, aged 13.
Alphonse said his son would have "random" violent outbursts, attacking him up to twice a day, but he became "conditioned to his behaviour" and "allowed him to abuse and assault me".
"I'm ashamed of my response," he said, adding his fear "prevented him from doing things a parent would normally do", such as restricting internet activity and ordering weapons online.
"This had catastrophic consequences for which I'm desperately sorry," he said.
"I accept I bear my share of the responsibility and that by not challenging his behaviour he was allowed to acquire dangerous weapons and view inappropriate content online."
He said he and his wife Laetitia Muzayire "couldn't set boundaries, we couldn't say anything because it would lead to outbursts, and he was effectively out of control". He also said he feared his son would be taken away.
Axel was referred three times to the government's anti-terror programme Prevent between 2019 and 2021 because of concerns over his fixation with violence, including school shootings.
The criminal investigation showed he had images of mutilated bodies, torture, cartoons mocking Islam, antisemitic material, Nazi mass graves and material demeaning to women and girls, on his devices.
His father told the inquiry he was not aware of the material but admitted: "I had lost control, I had no authority as a father."
"I was reduced to somebody who feeds him, does all he asks," he said, adding: "I had no power to stop him from accessing anything he wanted online."
The inquiry heard Axel received a delivery of a machete in June 2023 but his father said he didn't confront him "because he would fly into a rage".
Knife packaging found in washing machine after Rudakubana left home
His brother Dion said Axel would order packages online with money he made through his genealogy business which he feared "had something bad in them".
He told the inquiry the last time his brother left home alone before the Southport attack was when he was caught carrying a knife on a bus in March 2022, telling police he was "going out to stab someone to get rid of his social media accounts".
Dion said it would have seemed "logical" to Axel, adding: "It wouldn't have been anyone specific, just a random person."
A week before the mass stabbing, armed with a knife, Axel booked a taxi to his old school and tried to get in, but was stopped by his father.
Axel Rudakubana, was aged 17 when he murdered Elsie Dot Stancombe, seven, Bebe King, six, and Alice da Silva Aguiar, nine, in a knife attack on a Taylor Swift-themed dance class on 29 July last year.
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Eight other children, who cannot be identified because of their age, were also injured, along with yoga instructor Leanne Lucas, who was leading the dance class, and businessman John Hayes, who was one of the first people on the scene and tackled the killer.
Dion described the moment his brother left the family home that morning wearing a face mask and with the sleeves of his hoodie pulled down.
He told the inquiry how his mother showed him the knife packaging she found in the washing machine shortly after.
But his parents "didn't seem alarmed" and his mother went back to bed so he took "comfort" from this and there was "no discussion about contacting the police".
"We did not believe he intended to harm anyone" and thought if he was carrying a knife it was to "protect himself, not to harm others", Dion said.
Asked about why Axel may have targeted the Taylor Swift-themed dance class, Dion suggested because "children are very valuable to society" and it would "hurt society very badly" if children were to be harmed.
The inquiry, which is being held at Liverpool Town Hall, continues on Thursday.
(c) Sky News 2025: 'I'm desperately sorry': Axel Rudakubana's father accepts 'share of the responsibility
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