‘It remains unclear whether the Manchester bomber acted alone when preparing the device that killed 22 people, police have said.
The head of counter-terrorism in the region said Salman Abedi was likely to have built the bomb alone at his flat.
But it was “less clear” whether he had obtained and stored all the materials, or if others were “complicit”.
However, all 22 people arrested in connection with the attack in May have now been released without charge.
Detective Chief Superintendent Russ Jackson said the force now had a “deep understanding” of Abedi’s movements in the weeks leading up to the attack.
This included how the chemicals to build the bomb were obtained and where he put the device together.’