PALMER PARK, Md. — Federal officials are investigating allegations of discrimination against black and Hispanic officers in the Prince George’s County Police Department.

Police Chief Hank Stawinski announced the investigation in a letter to his officers Tuesday. Stawinski said he was notified that the Department of Justice is investigating whether the department violated Title VII, a federal law that prohibits employers from discriminating against employees on the basis of sex, race, color, national origin and religion.

Last year, a complaint was filed by the National Hispanic Law Enforcement Association and United Black Police Officers Association on behalf of 90 officers. It included several photos, including one of a training dummy with a black face pasted on it and an afro wig at its feet.

Stawinski said he will cooperate fully with the investigation.