The pose struck by the cadets, dressed in their gray uniforms while standing on the steps of barracks in late April, is seen by some critics as an implicit show of support for the Black Lives Matter movement and thus a potential violation of a Defense Department rule against "partisan political activity."

West Point seeks to portray itself as a melting pot that brings together talented students from across the country, without regard for racial or ethnic differences, for elite training as future military leaders.

Lieutenant Colonel Christopher Kasker, a spokesman for the academy in New York state, confirmed that the cadets were members of the current graduating class.

"Academy officials are conducting an inquiry into the matter," he said on Saturday.

The young women were following a longtime tradition at West Point, where soon-to-be graduates each year strike stern and straightlaced poses in historic style much as their predecessors have done for more than a century.