Some seriously injured victims of Arena bombing waited more than three-and-a-half hours for an ambulance North West Ambulance Service 'casualty clearing officer' James Birchenough said it took time to triage, treat and stabilise patients before they could be moved An ambulance at Manchester Arena following the attack (Image: PA) Some casualties of the Manchester Arena bombing had to wait more than three-and-a-half hours before they were dispatched to hospital, the inquiry into the atrocity has heard. The North West Ambulance Service operations manager who was allocated as the 'casualty clearing officer' on the night of the attack, James Birchenough, said time had to be spent triaging and stabilising patients before putting them into ambulances, although he accepted more staff would have speeded up the process.