MI5 missed ‘significant opportunity’ to prevent Manchester Arena bombing

The families of some of the victims described the findings as ‘devastating’ and ‘unacceptable’. Photograph: Phil Noble/Reuters

The failure of MI5 to act swiftly on crucial intelligence was a “significant missed opportunity” to take action that might have prevented the Manchester Arena attack, a long-awaited report on the atrocity has concluded.

Sir John Saunders, the chair of the Manchester Arena inquiry, said there was a “realistic possibility” that investigators could have thwarted the plot had they acted more decisively on two key pieces of evidence in the run-up to the bombing.