Assallamu aliakum, dear ulama, i want to know about the executing of so called "apostates and collaboraters" by beheading them. This has become the norm in iraq and it is filmed.

Is such a method allowed in islam, ive heard of beheading by stiking a single blow to the neck and instantly severing the head but to use a machete and cut through slowly n cause maximum pain to the victim seems far from the techings of jihad.

Any answers would be appreciated.