The UK's counter-terrorism agency, MI5, could have prevented the deadly Manchester Arena suicide bombing on May 22, 2017, had it responded more promptly to crucial information, according to a public inquiry led by retired Judge Sir John Saunders.
The suicide attack carried out by Salman Abedi, the son of religious extremist immigrants from Libya, at an Ariana Grande concert had left 22 people dead, and hundreds injured.
An MI5 officer admitted that the agency had procrastinated over two pieces of intelligence pertaining to the bomber, which were assessed at the time as not being terrorism-related. While agents mulled determining one as a possible pressing national security concern, they delayed discussing it with agency colleagues, said the report. Accordingly, the agents failed to write a report on the issue that same day.
"The delay in providing the report led to the missing of an opportunity to take a potentially important investigative action. Based on everything the security service knew or should have known, I am satisfied that such an investigative action would have been a proportionate and justified step to take. This should have happened," John Saunders said in his report.
Salman Abedi "demonstrated some security consciousness and this might have affected the efficacy of the investigative action that I have identified," Saunders added.
The inquiry, launched over three years ago, and containing oral evidence from 267 witnesses, concluded that "there was a realistic possibility that actionable intelligence could have been obtained, which might have led to action preventing the attack."
If MI5 had not overlooked the information that it had at the time, the agency could have apprehended Abedi at Manchester airport, where he flew in from Libya four days before the deadly bombing. The intelligence could have resulted in Abedi being tracked to the parked vehicle where he had hidden his home-made bomb, the report stated.
Salman Abedi could have been assisted in his devious plot by someone in Libya, the inquiry also determined, adding that it was not possible to identify who this accomplice might have been. A previous MI5 assessment had stated that only Salman Abedi and his brother Hashem were involved in the bombing plot.
This is the inquiry's third and final report into the suicide attack, with the first volume also having been made public, and the second availible only to those with a security clearance.
In response to the inquiry's findings, MI5 Director General Ken McCallum told the media that he was "profoundly sorry that MI5 did not prevent the attack."
"Gathering covert intelligence is difficult, but had we managed to seize the slim chance we had, those impacted might not have experienced such appalling loss and trauma," MI5 Director General Ken McCallum said in a statement.
Salman Abedi, a British citizen of Libyan descent, detonated a backpack with explosives at the entrance to the Manchester Arena as thousands of concert goers were leaving the show, including children. Ever since the attack, British security services have faced criticism for dropping the ball on the case. Salman Abedi had been probed by MI5 in 2014 and was later flagged by the agency's 'Operation Clematis' as worthy of further investigation.
Salman's brother Hashem Abedi was extradited from Libya and convicted in 2020 of the murders of all 22 victims for helping plan the attack and buying the bomb-making materials and the car where they were stored.