Axel Rudakubana did not appear out of the blue.

By the time he carried out the brutal murders of three young girls, the teenager was well known to police, anti-extremism authorities and a number of other public agencies.

But despite repeated concerns about Rudakubana’s taste for violence, there was only ever limited intervention.

The government now says several opportunities were missed to stop him turning his dark obsessions into a reality. Prime Minister Sir Keir Starmer said the state had failed.

This is what we know about his journey to becoming a killer – and whether it could have been prevented.

The first serious signs Rudakubana was capable of inflicting harm date back to when he was in year nine at Range High School in Formby, Merseyside.

At the age of 11, he had appeared in a BBC Children In Need campaign video, which he had been put forward for by an acting casting agency.

But over his adolescence, Rudakubana began to exhibit anger issues and a propensity for violence. Fellow pupils remember him being obsessed with figures such as Adolf Hitler and Genghis Khan.

His time at Range High School ended in October 2019 when he took a knife into school. It would later emerge he told the Childline call centre that he did so because he had experienced racist bullying.

Rudakubana did not use the knife on that occasion but the incident was serious enough that he was permanently expelled from the school.

He returned to the school about two months later with a hockey stick and attacked another child with it. He had to be restrained by staff.

From the point at which he was thrown out of Range High School, Rudakubana largely fell out of the formal education system.

Local health workers determined he had an autism spectrum disorder and he was later enrolled in two other schools for children with special needs: The Acorns School and Presfield High School & Specialist College.

He attended sixth form at the latter only for a few days and was largely dealt with by home visits. The school sometimes requested police accompany teachers when visiting his home, such were the concerns about his violent behaviour.

Lancashire Child Safeguarding Partnership said Rudakubana failed to “re-integrate” into education after his exclusion from Range High School, a situation “exacerbated by the pandemic”. His attendance, they said, was “limited”.

At around the same time it was noted Rudakubana experienced “anxiety which prevented him from leaving his home”.

During the years in which he stopped attending school, several local agencies had various levels of contact with Rudakubana.

He was convicted of assault and referred to the youth justice service after the incident when he took a knife into school. He completed rehabilitation activities aimed at young offenders who have pleaded guilty to a first offence.

However, Lancashire Constabulary had “several” further interactions with the teenager between October 2019 and May 2022 – including four calls from his home address relating to concerns about his behaviour.

On each occasion, officers made contact with MASH – a local grouping of agencies tasked with overseeing vulnerable people in the area.

Children’s Social Care carried out an initial assessment into Rudakubana, which found social work support was not required. It recommended “early help”, which covers forms of less intensive intervention.

Contact was made with Rudakubana and his family and they were offered guidance on his “emotional wellbeing and behaviours”.

He had involvement with local mental health services but “stopped engaging” in February 2023.

A spokesperson representing local agencies said his “participation and engagement remained a challenge” throughout this period, despite the efforts of professionals to engage with him.

An independent review into whether more could have been done to intervene is under way.

Rudakubana’s twisted interest in violence began to emerge both before and after the attack in Southport on 29 July 2024.

He came to the attention of the government’s anti-extremism Prevent programme because he had expressed an interest in school shootings, the London Bridge attack, the IRA, MI5 and the Middle East.

He was referred to Prevent three times between 2019 and 2021 over concerns about his interest in violence.

The full scale of his obsessions became clearer after the attack when his home and digital devices were searched.

Police found his devices contained images from conflicts in Gaza, Ukraine, Sudan and Korea, as well as copious academic material relating to war and genocide.

His search history revealed an interest in Nazi Germany, ethnic violence in Somalia and Rwanda, and slavery.

Detectives also found an American academic study of an al-Qaeda training document, which had been downloaded at least twice since 2021.

These twisted interests provide the backdrop to the horror that would unfold on 29 July.

On 7 July, an advert was posted on Instagram advertising a Taylor Swift-themed dance workshop for young children. It sold out within 11 days.

The class got under way at 10:00 BST and photos taken at the scene and reviewed by police show 26 children laughing and playing at the start of the school holidays.

At 11:10, Rudakubana left his home. His face was obscured by a hood and a surgical mask.

He was carrying a 20cm-long kitchen knife purchased on Amazon on 13 July. Police say he used encryption software to conceal his identity when he bought it.

Home Secretary Yvette Cooper has called it a “disgrace” that a teenager with a history of violence was able to easily acquire the blade. Amazon says it has launched an urgent investigation.

Shortly before leaving the house, Rudakubana deleted his IP address from his tablet, one of several pieces of evidence uncovered by police that revealed he took efforts to conceal his online movements. He also searched for material on the stabbing of a bishop in Sydney in April 2024.

A taxi picked him up at 11:30 and he stayed silent throughout the journey.

He left the car without paying and made his way to a garage. The driver followed him and there was a confrontation.

When the garage owner told him to pay for his ride, Rudakubana replied: “What are you going to do about it?”

Fifteen minutes later, he was inside the dance studio and began to stab at will.

His target – the most vulnerable people in society, young children – appeared to have been chosen to create the maximum horror and disgust.

Rudakubana killed six-year-old Bebe King, seven-year-old Elsie Dot Stancombe and nine-year-old Alice da Silva Aguiar. He tried to kill others by stabbing them in the back as they fled.

By 11:59 he had been arrested but said nothing when formally questioned by police.

In the days and weeks after the Southport attack, it became clear to investigators that Rudakubana was hell-bent on creating carnage and death, fuelled by his wide-ranging obsessions with human suffering.

When police searched his home, they found a cache of weapons, including a machete, a set of arrows and a sealed box containing an unknown substance. Tests at Porton Down, the government’s biological warfare laboratory, confirmed the substance was ricin, a poison for which there is no cure. There is no evidence he ever deployed it.

It has also emerged that one week before the murders, Rudakubana tried to return to Range High School, the scene of his expulsion five years earlier.

He was wearing the same hooded sweatshirt and surgical mask he would wear during the attack the following week, but was prevented from making the journey when his father pleaded with a taxi driver not to take him.

It is not known whether Rudakubana intended to attack people that day but his movements bear a striking similarity to the events of the following week. On that second occasion, he made sure to book the taxi after leaving the house.

The amount of information known before the murders about Rudakubana’s violent obsessions has prompted serious questions over whether more could have been done to stop him – in particular, whether Prevent could have acted.

Despite the three referrals over Rudakubana, it has been established concerns about him were never escalated up the chain, meaning he was not put under enhanced monitoring.

An urgent Prevent review carried out over the summer found this was because, while there was evidence he had an obsession with violence, he did not appear to fit the mould of a would-be extremist.

There were no signs of any allegiance to a single cause – which is why despite pleading guilty to downloading a terror manual, his case has never been treated as a terror investigation.

His case has prompted concerns over whether Prevent is equipped to identify dangerous people who fall outside the traditional view of what constitutes an extremist.

The urgent review found that, given Rudakubana’s age and complex needs, his case should have been escalated. It concluded Prevent put too much weight on his apparent lack of adherence to a single radical ideology.

The home secretary said the “cumulative significance” of Rudakubana’s three repeat referrals was “not properly considered” by Prevent, while Prime Minister Sir Keir Starmer said it was “clearly wrong” he was not deemed to meet the programme’s threshold for intervention.

A wider review of the Prevent programme is being carried out.

Rudakubana will be sentenced for his crimes on Thursday – but the questions posed by his descent into violence will be agonised over for years to come.