Firefighters have described the gruelling conditions they faced in their search for survivors of Hong Kong’s worst fire in more than seven decades, with rescuers climbing dozens of flights of stairs as they conserved oxygen to look for anyone alive on the higher floors. For some firefighters, the operation has left them with feelings of guilt and helplessness after they only found bodies. One said encountering the scattered corpses had given him nightmares that left him unable to sleep normally...