Law enforcement and counterterrorism officials are still investigating the possible “wider conspiracy” behind the May 22 Manchester Arena bombing, according to a statement released by the Manchester Police. Twelve men have been arrested in connection with the investigation and remain in custody. It is not known if charges will be brought against any or all of them. Two people, including one woman, were detained earlier, but released without charge.

Authorities have released images (seen above) captured by CCTV of Salman Abedi, the 22-year-old who detonated the bomb. The images are part of an effort to obtain more evidence regarding Abedi’s movements between May 18, when he returned to the UK from his travels abroad, until his night of terror days later. Forensic experts identified Abedi as the perpetrator within two hours of the attack. The Islamic State has claimed responsibility for the act.

The Manchester police released an infographic, seen on the right, summarizing key events to date.

Officials have discovered a flat where Abedi, and possibly his co-conspirators, may have assembled the bomb.

“The investigation is making good progress and we know one of the last places Abedi went was a city centre flat and from there he left to make his way to the Manchester Arena,” Greater Manchester Police Chief Constable Ian Hopkins and Deputy Assistant Commissioner Neil Basu, the Senior National Coordinator for UK Counter Terrorism Policing, said in a statement released online. “The flat is highly relevant as a location which we believe may be the final assembly place for the device.”

“In the past five days we have gathered significant information about Abedi, his associates, his finances, the places he had been, how the device was built and the wider conspiracy,” Hopkins and Basu said yesterday.

Authorities have not publicly confirmed that Abedi had co-conspirators, although that is the clear implication of their statements. “This is still a live investigation which is not slowing down,” Hopkins and Basu added. “Our priorities are to understand the run up to this terrible event and to understand if more people were involved in planning this attack.”

During an interview on BBC News with Andrew Marr, British interior minister Amber Rudd was asked about members of the “large group” surrounding around Abedi who have been arrested, and whether “some” members are sill at-large.

“Potentially, I mean it’s an ongoing operation” that is still at “full tilt,” Rudd responded.

Marr asked Rudd about possible security lapses in the lead up to Abedi’s bombing, including tips that authorities reportedly received, and failed to act on, beforehand. Rudd wouldn’t comment on the specifics, but defended the UK government’s counterterrorism record in general. She said that 18 plots have been foiled since 2013 and highlighted the “scale of the problem” Britain faces, especially from the Islamic State, which is trying to “weaponize young people in our society.”

Marr also inquired how many “serious potential jihadis” there were “across the country.” Citing figures provided by MI5, Rudd responded that the security services are “looking at 500 different plots” with 3,000 possible terrorists on the “top list” and 20,000 “underneath that.”

“But that’s all different layers, different tiers, and it might be just a question mark about one of them” that leads to inclusion on the “top list,” she explained. In other words, British authorities do not think that all of the people on MI5’s lists are necessarily terrorists in waiting. But officials are having a difficult time determining which individuals will follow Abedi’s path.

The British government has previously warned that the Islamic State threat is “unprecedented.” [See FDD’s Long War Journal report, Why the UK launched its first targeted drone strike ever.]

The Manchester investigation is massive effort, requiring significant resources all by itself. Approximately 1,000 members of the British security services and law enforcement have been involved.

Outside of the UK, officials are looking into Hashim and Ramadan Abedi (Salman’s brother and father, respectively), both of whom were detained in Libya last week. Libya’s Special Deterrence Force, Rada, alleges that Hashim Abedi has admitted foreknowledge of the plot and that he and his brother were both members of the Islamic State. The senior Abedi’s ties to the Libyan Islamic Fighting Group (LIFG), a designated terror group linked to al Qaeda, are also being explored. [See FDD’s Long War Journal report: Analysis: UK investigating possible ‘network’ behind Manchester attack.]

Thomas Joscelyn is a Senior Fellow at the Foundation for Defense of Democracies and the Senior Editor for FDD's Long War Journal.

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