Manchester terror attack: All 22 suspects arrested for concert blast freed without charge

People attend a vigil for the victims of attack at a pop concert at Manchester Arena, in central Manchester. Reuters[/caption]Salman Abedi detonated a knapsack bomb as crowds were leaving an Ariana Grande concert on 22 May, killing 22 people. He also died.Shortly after the attack, police said they had rounded up members of Abedi's network. But Greater Manchester Police say all 22 suspects have now been released without charge.Russ Jackson, head of counterterrorism policing for northwest England, said on Sunday that police believe Abedi assembled the bomb himself, but it's unclear "whether he acted alone in obtaining the materials for the device."He said the investigation will continue "as we work to understand the full extent of the involvement of anyone else."