She had been so busy talking that she didn't notice when the barrier cracked and was pulled down. It had to do with the exorcism going on.
A heavy wind, strong enough to pull down any building was was brewing. He didn't know what was happening to Magdalene but he could tell it wasn't good. When Hannah had gotten distracted he moved in his vampire speed and caught her throat before she could comprehend what was happening. He lifted high up in the sky with his one hand and she choked struggling to break free. She brought her staff forward to strike him but the his nails grew longer piercing her neck making her spill blood. He brought his other hands to her mouth digging his nails in, she tried to scream but in one aggressive move he ripped off her head from her neck and blood splattered to his face. Dropping her head to the ground he stepped on it to crush it beyond imagination. You can never tell if she could get her head back to her body.