Really? I was not aware chemical weapons tear people to pieces. That’s rather strange.
Chemical weapons can cause skin boils/damage but they do not ‘tear’ peaple to pieces. Depending on the toxin used, there could potentially be little or no external damage to the bodies. The nerve gasses just shut down muscle function.
A bombardment containing both chem and explosives would. Chem weapons to make defenders try to leave their positions to get away, then hit with explosives when they're out in the open running from the chem attack.