In a place like Afganistan, mostly, but in others, such as Turkey, Syria, Iraq, Yemen, Egypt and Sudan, Indonesia, etc, the victims are other Islamic sects (Shiite), other ethnicities/races (Sub-Saharan Africans, Sunni Kurds, etc), and people of other religions, from Animists to Zoroastrians.
Also, Al Queda and ISIL, amongst others, consist of many foreigners.