The vehicle ramming and knife attack carried out by three jihadists on London Bridge on June 3, 2017, killed eight people and injured 48, ending only when the police shot and killed the attackers. This was the third most fatal Islamist attack in the UK to date and the most significant attack in London since the 2005 transport bombings. In response to the attack, the government held a public inquest, including interviews with the attackers’ acquaintances, the security services and police, and technical experts. When the hearing concluded on June 28 of this year, it became one of the most comprehensive public inquiries ever held in the UK, shedding new light on the perpetrators, their paths to radicalization, pre-attack planning, and on the attack itself. The report aims to gather this material together to provide insights into the attack and the prior events. 
The eventual leader of the London Bridge attack, Khuram Butt, was born in Pakistan in 1990 and brought to the UK with family by his father in 1998. However, Butt’s father died in 2003 when he was 13. This left him without a father figure, and—as for many other radicals—this may have made him more receptive to charismatic extremists. Butt subsequently performed relatively well at schools in London, but upon leaving took a succession of short-lived jobs, including in a removals firm, at a pizza outlet, and as an office assistant. In December 2013, he had an arranged marriage to Zahrah Rehman, a conservative British-Pakistani woman; their wedding day was the first time that they had met as adults. Shortly after this point, in 2014, which coincides with the rise of Islamic State (IS) in Iraq and Syria and their glorification of violence through social media, Butt became more overtly religious, including attempting to convert colleagues to Islam, and saying that he wanted to leave the UK—perhaps to Turkey—to live in a more Islamic environment.
Some of this radicalization appears due to Butt coming increasingly under the influence of followers of al-Muhajiroun, the main British pro-jihadist group, which has operated under numerous other names. This includes at some point encountering and visiting the home of its leader, Anjem Choudary, who he reportedly found inspirational. He further exposed himself to radical ideas through listening online to extremist preachers such as the Jamaican Abdullah Feisal and Ahmad Musa Jibril, watching IS videos and propaganda and being part of a WhatsApp group chat used by other British extremists. By around the peak of IS’ power in mid-2014, Butt became significantly more radical, describing Shias as “non-Muslims”, criticizing his family’s traditional Pakistani cultural practices, and telling one friend, Hamza Raza, “You are not supposed to follow the rules in the country that you are in, you are supposed to listen to your own Islamic rules and regulations,” as well as advocating the need for Sharia law. Also in 2014, around a year after the death of Lee Rigby—an off-duty British soldier killed by jihadists in London—Butt described the murder to a colleague as an “eye for an eye,” and elsewhere criticized U.S.-led attacks on IS. However, other accounts given to the inquiry, from the same period and until as late as 2016, record Butt also listening to music and smoking cannabis, both usually viewed as forbidden by Islamist hardliners. However, such apparent contradictions are not unusual in accounts of radicalizing jihadists; both drug-taking and religious extremism can be seen as forms of escapism or as ways of rebelling against society.
As a result of this exposure to more radical individuals, media, and ideas, Butt became more committed to his hardline beliefs. Most notably, in February 2015, Butt planned to take his family to Turkey—perhaps to join IS in Syria—but his wife’s family became aware of the plans and seized his passport. Further evidence of Butt’s deepening radicalization came in July-August 2015 when he was filmed by a TV crew recording a documentary, “Jihadi Next Door,” which showed him praying in front of a black flag similar to that of IS alongside other British jihadist sympathizers. Elsewhere, he defended IS atrocities, causing arguments with a number of acquaintances. In response to this deepening radicalization, on September 30, 2015, Butt’s brother-in-law, Usman Darr, telephoned the Police Anti-Terrorism Hotline and reported his concerns about Butt. Butt was being investigated by MI5 around the same time, but surveillance resources were shifted away from him to other suspects as he was assessed to not be involved in actively planning an attack.
Meanwhile, however, Butt was becoming more volatile. This included arguing with imams of local mosques that he felt were too moderate and on one occasion in July 2016 physically attacking a prominent local Muslim leader, Usama Hasan, a former hardline Islamist who had since joined the anti-extremist Quilliam Foundation and publicly advocates for more moderate interpretations of Islam. Butt was arrested and interviewed over this incident, but he was not charged.
A critical turning point in the development of the London Bridge plot occurred in mid-2016 when Butt joined an East London gym, the Ummah Fitness Centre, which was popular with numerous jihadist sympathizers. Through the gym and its network of radicals, Butt met Rachid Redouane, a Moroccan who had moved to London after living in Ireland for several years, where he had married an Irish woman (who he had met in a nightclub) and had a son. Redouane, however, despite adopting some radical views, had never been specifically investigated by the British or Irish police or security services and had also never been convicted of any other criminal activity. In other words, he was a “clean skin” whose association with Butt was no reason to raise particular alarm bells. This, in retrospect, can be seen as a critical reason why the UK security services never identified their emerging cell.
However, through the same loose network of radicals associated with the Ummah Fitness Centre, Butt also met Youssef Zaghba, who would become the third London Bridge attacker and was only 22 at the time of the attack. Zaghba had a conservative Moroccan father and Italian mother and lived sporadically between the two countries. Zaghba’s family said that he was radicalized relatively rapidly around 2014-2015 due to unknown influences, and in March 2015, attempted to travel to Turkey to enter Syria and join IS, which he had come to see as running an ideal Sharia-governed state. Zaghba’s plans failed, however, when Italian police at Bologna airport prevented him from catching a flight to Istanbul after he told them his reason for traveling was to be a “ terrorista,” which he rapidly corrected to “turista.” Italian police added him to a Europe-wide database for suspected criminals, but when this triggered alerts when he entered the UK twice in 2016 and again in 2017, the UK and Italian authorities failed to liaise correctly. This meant that, despite his attempt to travel to Syria, he was not tracked by the UK security services during his subsequent time in London, during which he appears to have increasingly come under Butt’s ideological and social influence.
The small group of Butt, Redouane, and Zaghba, according to what is currently known, do not appear to have discussed their plans to carry out an attack with anyone else or to have sought to make contact with IS in Iraq and Syria prior to the attack. Indeed, their plan seems to have been inspired by the Nice and Berlin vehicle-ramming attacks of 2016 and the Westminster Bridge attack three months earlier in March 2017, in which a jihadist killed four people. That said, it is possible that evidence of such links between the attackers and a remote IS contact may emerge in the future, as has happened with previous cases which initially appeared to be “lone wolf” or “lone wolf pack” operations.
It appears that in the few days leading up to the attack, Butt took some steps to avoid raising any red flags with the authorities. For instance, he acquired the hired van which was used in the attack by paying £160 ($200) in cash to a neighbor who then paid for it online on his behalf; Butt having convinced him that he did not have enough money in his own account. Meanwhile, Redouane on May 15, 2017—two weeks before the attack—purchased three 12-inch ceramic kitchen knives from a discount shop. Redouane had arguably the lowest profile of the group’s members, and he may have made the purchase for this reason. The group also acquired an additional mobile phone, which they used to make some operational arrangements.
London Bridge was likely chosen as the target, concluding statements at the British inquest said, as it had no barriers between pedestrians and vehicles and relatively light traffic, meaning that a vehicle could reach a high speed. Moreover, the timing of the day—early evening on Friday night and shortly after a major soccer game had finished—meant that the bar and restaurants area near the bridge would also be well-attended. There is also evidence from the group’s phones that they had planned to conduct their attack on Oxford Street, a main shopping area, but picked London Bridge as a target of opportunity while enroute. Prior to launching the attack, the three strapped mock explosives belts to themselves—perhaps to create additional fear or else as a form of ritual act of homage to previous suicide bombers—and attached their knives to their wrists using tape. They then drove their van along the pedestrian sidewalk of London Bridge, hitting various people before colliding with a barrier. They then exited the van and immediately attacked people with knives before moving to nearby bars and restaurants. Here they carried out further stabbings before being shot dead by police, less than 10 minutes after commencing their attack.
The inquest showed that the radicalization of the individuals involved in the London Bridge attack involved a range of elements common to other militant plots. These include the presence of a central organizing figure able to inspire other followers to act, the critical influence of online radicalization, and the fact that the rise of IS in Iraq and Syria—and the international community’s strong military response to it—helped to turn extremists into militants, even if IS was not directly involved in the attack planning. Other key ingredients in the plot include the attackers employing some small elements of operational security, for instance disguising their hire of the vehicle used in the operation, which would have made the attack difficult to detect and prevent even if the individuals were being monitored. If there is any single lesson to learn from the attack, it is that Western security services will continue to face significant challenges in identifying and disrupting low-tech plots. This will particularly be the case when the attacks are planned by a small and tight-knit group of extremists who take steps to conceal their plans, use everyday objects as lethal weapons, and have little or no direct contact with known militant groups or individuals abroad.
 All material in this report is drawn directly from inquest. Full transcripts of the hearings are available here: https://londonbridgeinquests.independent.gov.uk/