OKLAHOMA CITY (AP) — A group of parents, faith leaders and a public education nonprofit sued Monday to stop Oklahoma from establishing and funding what would be the nation’s first religious public charter school.

The lawsuit filed in Oklahoma County District Court seeks to stop taxpayer funds from going to the St. Isidore of Seville Catholic Virtual School. The Statewide Virtual Charter School Board voted 3-2 last month to approve the application by the Catholic Archdiocese of Oklahoma City to establish the school, and the board and its members are among those listed as defendants.

The vote came despite a warning from Oklahoma’s Republican attorney general that such a school would violate both state law and the Oklahoma Constitution.

The Rev. Lori Walke, senior minister at Mayflower Congregational Church in Oklahoma City and one of the plaintiffs in the case, said she joined the lawsuit because she believes strongly in religious freedom.

“Creating a religious public charter school is not religious freedom,” Walke said. “Our churches already have the religious freedom to start our own schools if we choose to do so. And parents already have the freedom to send their children to those religious schools. But when we entangle religious schools to the government … we endanger religious freedom for all of us.”

The approval of a publicly funded religious school is the latest in a series of actions taken by conservative-led states that include efforts to teach the Bible in public schools, and to ban books and lessons about race, sexual orientation and gender identity, said Rachel Laser, president of Americans United for Separation of Church and State, which is among several groups representing the plaintiffs in the case.

“We are witnessing a full-on assault of church-state separation and public education, and religious public charter schools are the next frontier,” Laser said.

Oklahoma’s Republican Gov. Kevin Stitt earlier this year signed a bill that would give parents in the state a tax incentive to send their children to private schools, including religious schools.

The Archdiocese of Oklahoma said in its application to run the charter school: “The Catholic school participates in the evangelizing mission of the Church and is the privileged environment in which Christian education is carried out.”

Rebecca Wilkinson, the executive director of the Statewide Virtual Charter School Board, said in an email to The Associated Press that the board hadn’t been formally notified of the lawsuit Monday afternoon and that the agency would not comment on pending litigation.

A legal challenge to the board’s application approval was expected, said Brett Farley, the executive director of the Catholic Conference of Oklahoma.

“News of a suit from these organizations comes as no surprise since they have indicated early in this process their intentions to litigate,” Farley said in a text message to the AP. “We remain confident that the Oklahoma court will ultimately agree with the U.S. Supreme Court’s opinion in favor of religious liberty.”

Stitt, who previously praised the board’s decision as a “win for religious liberty and education freedom,” reiterated that position on Monday.

“To unlock more school options, I’m supportive of that,” Stitt said.