CHICAGO (CBS) — The CEO and co-owner of Second City is stepping down amid accusations of institutional racism at the famed theater.

In a letter posted on the Second City website, Andrew Alexander said he failed to create and “anti-racist environment.”

Alexander’s resignation comes after actor Dewayne Perkins said the company created obstacles for performers of color.

Alexander also said in his letter the next executive director of Second City will be a person of color.