Administrators at a Howard County school are trying to silence Arab, Middle Eastern, Muslim and South Asian students who are speaking up in support of Palestine, the ACLU of Maryland said in a letter Tuesday.

The letter, which focuses on River Hill High School, said Principal Robert Motley and Assistant Principal Allison Volinsky are violating district policy and the First Amendment rights of the students.

Nick Steiner, senior attorney at the advocacy organization, wrote in a letter to the Howard County Public School System superintendent that students and their parents say issues started last October, when a Hamas attack fueled Israeli retaliatory airstrikes.

The offensive has left more than 36,000 Palestinian dead and has driven more than 85% of the population from their homes.

The Howard County Public School System said in a statement that the concerns raised by the ACLU will be investigated and that students, staff or families to submit any complaints of discrimination to the administration.

According to the letter, students from two River Hill high school organizations — Muslim Students Association and Arab Students Association — wanted to take part in a national walkout. The letter says the administration initially did not let them, saying that the walkout was “too political” and “partisan.”

After five meetings, students were allowed to participate in a walkout on Nov. 8 under “strict conditions,” according to the letter. Students could only use “anti-war messages” and could not say the words “Palestine,” “Gaza,” “apartheid,” or “siege.”

Volinsky also asked the Muslim Students Association to remove posts from Instagram that expressed solidarity with Palestine, according to the letter. She also said students were not allowed to wear a pin on school grounds that said, “From the river to the sea, Palestine will be free,” saying that the phrase called for the “death of all Jews.”

The letter also said the administration did not check on the well-being of students and their families. One student has lost five immediate family members, 45 extended family members and dozens of family friends over the last few months in Gaza, according to the letter.

Steiner said in a letter that the advocacy organization is going to continue to monitor the school system, suggesting that the high school “takes measure to protect students,” including a suggestion a student had earlier this year of having a statement about the deadly impacts of Islamophobia in morning announcements.

Last October, then-superintendent Michael Martirano said he was “deeply saddened” by the Hamas attack and the war in Gaza, adding that he met with the Jewish Federation to talk about how to support students. He said he was concerned about the rise of hate bias and encouraged students to speak out.

Martirano issued another statement the following day, saying the Office of Diversity, Equity and Inclusion had also reached out to Muslim community leaders about the rise in Islamophobia and to ”ensure an open dialogue and continued partnership” with supporting students in the school system.