A brother and sister in California have been banned from their high school because they refused to wear masks on the first day of school, according to reports.

The father of the siblings, Gary Nelson, told NBC that his children were sent home from Springs Charter Schools Temecula Student Center and “told not to come back with or without a mask.” And if they returned, “they would be charged with trespassing.”

Nelson said the teens were not expelled from the school and were told they could continue their studies at home, NBC reported. However, Nelson said the teachers have been less than helpful to their needs.

On Aug. 19, Victoria, a junior, was advised to go to the principal’s office after showing up without a mask on, but the principal was not in, so she returned to the classroom, Nelson told the network. The father said the teacher then evacuated the classroom and called police. Victoria was confronted by a school resource officer and told to leave campus hours after the incident began, Nelson said.

The school then went into a “soft lockdown,” according to an email sent to parents by an assistant principal, and Victoria and brother Drew, a senior, were ordered to leave the school’s campus, NBC reported.

The siblings told NBC that they refused to wear masks because of their religious beliefs.

“The Bible says we’re made in the image of God and Satan tries to cover that up. A mask is a sign of oppression,” Nelson told NBC on Thursday. “If it was Muslim, Jewish or something of a more high-profile minority religion in this country, yes, they would have accommodated ... just to say they weren’t discriminating based on that religion. But they feel safe because it’s Christianity.”

It is not a Christian belief to refuse to wear a mask, according to NBC.

Principal Rebecca Fabozzi wrote in a letter to Nelson, “Each of your students refused to comply with the CDPH mask mandate for public schools. When asked by staff to wear a face covering, your students refused to comply,” NBC reported.

“When asked to leave the school ... and continue the day on home independent study, your student refused to leave the campus. Our resource officer arrived, and your student was directed to leave campus,” Fabozzi’s letter continued.

Victoria told NBC the ordeal has been unsettling.

“It’s hard to stand up for what’s right. We chose to not wear a mask because it’s not just an excuse. It’s truly what we believe in.”