Shemot 2:11-12

And it came to pass in those days, when Moshe was grown, that he went out unto his achim, and looked on their sevalot: and he spied an Egyptian striking an ish Ivri, one of his achim. And he looked this way and that way, and when he saw that there was no ish, he killed the Egyptian, and hid him in the chol (sand).