Rosebud, S.D. ? Sonny One Star says he learned not to cry or scream when he was beaten and sexually assaulted at his Roman Catholic boarding school on the Rosebud Sioux Indian Reservation.

Four decades later, he says it is time for a different approach.

“Today, I’m ready for retaliation,” said One Star, a leader on the reservation.

He and five other Sioux are suing the federal government for $25 billion on behalf of perhaps thousands of students allegedly abused at Indian boarding schools around the country. They hope to have the case certified as a class-action.

“The nuns and the priests — the ones who are still living — I just want to let them know I’m coming after them,” said One Star, 46, who attended the St. Francis Mission school, one of the three Catholic schools named in the lawsuit. “It was fun for them back then, but I want to get justice. I want to get even.”

Gary Frischer, a Los Angeles consultant working on the case, said preparation for the legal action started last year amid news accounts that Catholic dioceses across the nation were settling lawsuits alleging abuse by priests. Little was being said about abuse in Indian schools.

Over the past century, hundreds of thousands of Indians attended boarding schools under a federal effort to assimilate Indians into white society.

Tribal leaders often asked religious organizations to start boarding schools on reservations so that children would not be sent far away. Most of the schools were Catholic; most were closed or transferred to tribal control by the 1970s.

The lawsuit, filed in April in the U.S. Court of Federal Claims in Washington, accuses the government of failing to live up to treaties dating to the 1800s requiring it to protect tribes from, as the treaties put it, “bad men among the whites.”

Sonny One Star describes the physical and sexual abuse he encountered more than 30 years ago while attending the St. Francis boarding school near Rosebud, S.D. He and five other Sioux have filed a lawsuit seeking 5 billion in damages from the federal government on behalf of students who allegedly were abused at Indian boarding schools around the country.

The lawsuit also argues that the government set up the boarding school system in the late 1800s to try to wipe out Indian culture and language.

A spokesman for the Justice Department said federal officials would comment on the allegations only in court. The department’s answer to the lawsuit is expected in August.

Sherwyn Zephier said he and other students were beaten with boards and leather straps at St. Paul’s in Marty, the headquarters of the Yankton Sioux Tribe. Students also were forced to hold heavy books with their outstretched arms or kneel with their knees placed on broomsticks, he said.

“They did it in the name of God,” said Zephier, now a teacher at the tribal school that replaced St. Paul’s. “All that pertained to our culture was evil. They were trying to torture it out of us.”

One Star said when he was a first-grader, a nun would keep him inside during recess to punish him for speaking English poorly. He said she took him into a closet, made him drop his pants, raised her dress and hummed church hymns while sexually abusing him.

One Star said he later was beaten regularly with a wooden paddle and sexually assaulted by priests who grabbed boys out of bed in the dormitories.

“You could hear a pin drop when they came after you because everybody was listening. Then they’d turn the music up loud so you wouldn’t hear the cries, you know,” One Star said.