Is it permissible to burn a live sea snail (Bussur) shell with fire to extract it, and is this considered tormenting it?

If lighting a fire on the shell causes the animal to exit it when it feels the heat, then there is no harm in that. Scholars have permitted hunting locusts with fire, and some have permitted grilling fish alive, while others have disapproved of it. Torturing fish with fire is disliked because it is possible to let them die quickly, unlike locusts which have no blood and do not die quickly. Malik permitted cutting a whale alive or throwing it into fire while alive, and likewise, it is permissible to throw locusts into oil alive.