The Charles County branch of the NAACP has filed an official discrimination complaint with the Maryland State Human Relations Commission against a regional police training academy.

According to NAACP chapter President Gerald R. Watson, his office has asked the commission to determine why the Southern Maryland Training Academy has failed to hire any black instructors.

The academy is run by the Charles County Sheriff's Department and helps to train local, county and state police.

Capt. Ross Pitrelli, assistant to Sheriff David Fuller, said yesterday that the NAACP's complaint was "ridiculous." Pitrelli said none of the 15 academy instructors provided by the sheriff's department is black, but he said three black instructors recently left for medical reasons or were transferred.

Pitrelli, who ran the academy from its beginning in 1980 until last year, said, "We are prepared to sit down with anybody and defend our department's equal opportunity for all officers."

The NAACP complaint was its second in the last two months involving the sheriff's department. Last month, the civil rights group asked the State Human Rights Commission to investigate allegations of discrimination against blacks in the department's promotions, discipline practices and job assignments.

Watson declined to disclose the specifics of those allegations except to say they were made by black officers in the department.