Is Iblis one of the angels or one of the jinn?

Iblis was not an angel; rather, he was one of the jinn. This is indicated by the words of Allah Almighty: (And [mention] when We said to the angels, "Prostrate to Adam," so they prostrated, except for Iblis. He was of the jinn and disobeyed the command of his Lord). And Al-Hasan Al-Basri said: "Iblis was never an angel for the blink of an eye. Indeed, he is the origin of the jinn, just as Adam, peace be upon him, is the origin of humankind."