A class-action lawsuit filed Thursday accuses Pop Warner football of not monitoring games, practices, rules, equipment and medical care “to minimize the long-term risks” associated with brain injuries and repetitive hits to the head, according to court documents obtained by The New York Times.

The suit, filed in U.S. District Court in California, takes on the nation’s largest youth football program, accusing it of knowingly putting youngsters in danger by ignoring the risks of head trauma — a landmark case in that it pushes the legal battle over brain injuries in football to the game’s grassroots level.

Notes The Times:

“Unlike other cases that have centered only on football leagues, the complaint also accuses USA Football, the youth football arm of the N.F.L., and the group that creates football helmet safety standards (the National Operating Committee on Standards for Athletic Equipment) of failing to protect young players from the dangers of brain trauma and the long-term consequences of repeated head hits, and ignoring medical research that underscores the dangers of playing football.”

The lawsuit — brought by the mothers of two dead former football players — claims that Pop Warner players going back nearly two decades are entitled to an unspecified amount of monetary damages.

The complaint comes as the NFL, NCAA and individual colleges and universities are facing legal challenges on multiple fronts.

Moreover, Pop Warner — like high school programs in many states — already is facing a drop in participation as parents become increasingly concerned about the long-term damage caused by hits to the head, even those described in the lawsuit as “sub-concussive.”

The California suit also accuses Pop Warner of not approving the best equipment available and failing to accurately diagnose brain injuries, while alleging that the organization and the other defendants “acted with callous indifference.”

Pop Warner recently has settled multiple individual lawsuits brought by families of players who suffered significant head injuries, some of whom died from the injuries.