Mayor Sadiq Khan speaks at a vigil at Potters Field Park on June 5, 2017. Clodagh Kilcoyne / Reuters

Police have released the names of two out of three suspects in Saturday’s deadly terrorist attack on the London Bridge. One of the attackers, 27-year-old Khuram Butt, was a supporter of al-Muhajiroun, an Islamist group banned by the United Kindgom that operates under multiple aliases. Before October of last year, Butt worked as a trainee customer services assistant for the London Underground. Although Butt was a British citizen living in east London, he was born in Pakistan, with his parents hailing from the nation’s Punjab province. He and the woman believed to be his wife have two young children, a boy around three years old and a newborn.

In recent hours, both authorities and local residents have pointed to Butt’s suspicious behavior leading up to the attack. “There were some red lights flashing” Michael Clarke, the former director general of a security think tank, told the BBC. In the summer of 2015, Butt was the subject of an investigation by London’s Metropolitan Police and MI5, the UK’s domestic counter-intelligence and security agency. Around the same time, Butt was said to be urging people at his local mosque not to vote in the upcoming democratic election. His actions prompted a concerned member of the public to report him to the UK’s anti-terrorism hotline. After detectives found no evidence that Butt was planning an attack, they moved his case to a lower priority level. In 2017, Butt was seen exhibiting similar behavior outside the same mosque.

On Monday, Mohammed Shafiq, the head of a Muslim organization in Greater Manchester, told the BBC that Butt had verbally assaulted him in 2013, calling him a “traitor” and “a government stooge.” “I am not surprised that Khuram Butt carried out the terrorist attack,” Shafiq said. In 2015, one of Butt’s neighbors also reported him to the police after she found him attempting to radicalize children at a local park. In 2016, Butt appeared in a documentary called The Jihadis Next Door, which centered on a group of British Islamist extremists with ties to the hate preacher Anjem Choudary.

Details regarding the second attacker, Rachid Redouane, were less readily available, given that Redouane was not a terrorist suspect prior to Saturday’s attack. Authorities report that Redouane was a 30-year-old chef who claimed to be Moroccan and Libyan. According to Ireland’s RTE news site, Redouane married his now-estranged wife in Ireland in 2011 before returning to the UK. His wife is reportedly of Irish heritage and never converted to Islam. A source who knows Redouane’s family recently told The Guardian that the attacker “wasn’t sociable” and “didn’t get involved in any of the [neighborhood] activities.”

All three attackers were shot and killed by police on Saturday night. The Independent Police Complaints Commission (IPCC), a police watchdog in England and Wales, said Monday that 46 shots were fired by eight police officers. Following the attack, twelve additional suspects—seven women and five men—were arrested due to their supposed connections, but all of them have since been released without charge. It is unclear which suspect was behind the wheel of the white van that sped into pedestrians on the London Bridge, killing seven people and injuring 48. Police have since reported that the suspects were wearing canisters around their chests to mimic explosives. At least one of the suspects also fled the scene and began stabbing people at random at a nearby area filled with bars and restaurants.

Authorities are now working to confirm the identities of the deceased victims. On Monday, the family of Christine Archibald, a woman from Canada who was living in Europe with her fiancee, mourned the loss of “our beautiful, loving daughter and sister.” The family of James McMullan, a 32-year-old man from east London, also expressed their grief, believing their loved one to be dead. McMullan’s bank card was reportedly discovered on the body of one of the victims. Another unnamed French citizen was also confirmed dead by France’s foreign minister.

On Monday, a vigil held in remembrance of the injured and deceased at Potters Field Park attracted thousands of people. Many attendees left flowers and handwritten notes, while others held signs expressing their love for the city. London Mayor Sadiq Khan, Home Secretary Amber Rudd, and the Archbishop of Canterbury, Justin Welby, were all in attendance. While addressing the crowd, Mayor Khan, whose response to the attack drew criticism on Sunday from U.S. President Trump, shared a stern message for Islamist extremists. “As a proud and patriotic British Muslim I say this, you do not commit these disgusting acts in my name,” Khan said. “Your perverse ideology has nothing to do with the true values of Islam. You will never succeed in dividing our city.”

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