Is it permissible to use an electric mosquito and fly swatter, or do the conditions of burning with fire apply to it?

The electric fly swatter for insects does not burn with fire, and the insect's death by it is through electrocution, not burning. The use of these traps is permissible out of necessity, especially if harmful insects are numerous, and this is not part of the forbidden torture by fire. This is because torture by fire is the intent to inflict pain, whereas destroying a harmful creature with fire is permissible if no other means are available.