Nazir Afzal, Chief Crown Prosecutor for CPS North West, spoke outside Preston Crown Court following the sentencing of Dale Cregan.
One-eyed police killer Dale Cregan is set to die in prison with a whole life sentence for murdering four people in Greater Manchester after his long-running trial came to an end.
Cregan, 30, had previously pleaded guilty during the trial to killing policewomen Nicola Hughes, 23, and Fiona Bone, 32, and father and son David Short, 46, and Mark Short, 23, last year.
He also admitted the attempted murders of three others and causing an explosion with a hand-grenade.
A jury at Preston Crown Court found him not guilty of one remaining count of attempted murder involving a grenade attack on Sharon Hark, which he denied.