Movie does identify her background and motive as Muslim
That scene where she's cleaning herself gives it away to anybody versed in Islamic theology. It's well documented that Muslim suicide bombers and so called Islamic 'holy warriors' clean their bodies before they begin their mission. They need to go to paradise clean and pure.
Without the Islamic religious element it makes no sense for a person to preen themselves before death. A suicide bomber is not going to leave a pretty physical corpse no matter how well the suicide bomber grooms. The cleaning is symbolic for Muslim terrorists.