CHICAGO (AP) — A federal lawsuit filed Tuesday alleges two security guards who worked at a public high school in suburban Chicago had sex with female students, and the school failed to adequately protect girls from purported predators.

The 22-page suit says school officials knew or should have known the staffers posed a risk at the 3,600-student Evanston Township High School campus. The lawsuit was filed on the eve of a new school year beginning Wednesday, and months after the school settled litigation alleging a former drama teacher abused several male students in the 1970s and 1980s.

Local m...