Egpytian Police Kill Two Africans. What are they?

Check out this story in Isreali Daily Haaretz. Egyptian police have been killing citizens of sub-Saharan countries trying to cross into Israel in search of employment opportunities. Why in the world are they shooting these migrants! Are they similarly killing Arabs, Egyptians, or Palestinians in the same position? Furthermore, for anyone who doesn't think race is an issue here, why are the Egyptians describing the migrants as "Africans," as though they themselves are not? Substitute "Africans" with "blacks."