This is unfortunately not unexpected as it touches the Revolutionary Guard, which is a separate State in Iran. But sadly we see this in most States when the military's are involved in shooting down an airliner either voluntarily (e.g Israel with LN114, , USSR with both Koreans, ) , or by mistake ( e.g. France with AF1611, Italy with Itavia870 , Russia with MH17, etc...) It often takes decades to get a vague idea of the truth and it generally come from investigation journalism rather that the local Accident investigation Bureau.