Dozens of students walked out of a New Jersey high school in protest after a video went viral showing a teacher telling her class to “speak American” rather than Spanish.

The students walked out of Cliffside Park High School, according to WPIX,  in response to an episode in a classroom in which an unnamed teacher substituting in a math class said that soldiers are “not fighting for your right to speak Spanish.” Rather, she said, “They are fighting for your right to speak American.”

A few students immediately walked out of the class, with one student telling the teacher she was prejudiced, and a short time later dozens of students left the school in protest, WPIX reported. At some point, a fire alarm was sounded and the school was temporarily evacuated.

It was not the first time this unnamed teacher had told students to stop speaking Spanish, the station reported, quoting a freshman named Omar Toledo as saying, “She would usually be in the hallways and tell you not to speak Spanish.”