SAN FRANCISCO (CBS SF) — An anti-racism lesson being presented to online to students from Lowell High School in San Francisco was interrupted by a series of racist and anti-Semitic slurs and pornographic images, according to the school district.

The San Francisco Unified School District said on Wednesday that students were using a virtual bulletin board known as Padlet to share their reflections on a series of anti-racism lessons when the racist and obscene messages appeared among the submissions. The Padlet session, which is moderated by staff members, appeared to have been hacked and the district said administrators immediately deactivated the Padlet.

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The district’s Department of Technology is now trying to trace the origin of the offensive posts. A letter was sent to all students and families about the incident, inviting anyone with information to come forward.

“On the same day that we were offered some semblance of hope or renewal, our very first Black female vice president taking the oath of office, our students are dealing with a system that allows for such blatant racism to run rampant in our schools,” said San Francisco Board of Education president Gabriela López in a prepared statement.

“We know that these platforms are only open to SFUSD accounts and we’re really careful about that to make sure that it’s within our school district, which leads us to believe that it was kids within our school district,” López told KPIX.

Students at Lowell have long complained about ongoing racism at the elite school where less than 2% of the students at Lowell are Black. Nearly 70% are either Asian American or White, while 12% are Hispanic.

“People calling me N-word with a hard r, you know, micro aggressions, asking why am I here, you don’t belong at Lowell. Harassment images comparing me to a gorilla — it’s a lot of stuff that gets swept under the rug at this school,” said student Shavonne Hines-Foster..

“When I first saw the post, I definitely wasn’t surprised because racism at Lowell is definitely there,” sophomore Gabrielle Grice said.

Lowell is one of few public schools in the country where admissions are merit-based. Admissions for the 2021 academic year will be determined by a lottery because 7th and 8th grade academic scores are not available because of the pandemic.

López said the district needed to address the anti-Black racism in its schools and “especially those with selective enrollment.”

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“This incident is unfortunately not an isolated one and is an indication of the deeper problems our District must address,” said López. “In 2016, students staged a walkout after the administration failed to address racist imagery posted in the school. Their demand remains unmet five years later. This past fall, we witnessed more of this behavior, a Black student leader was shouted down while making comments during a Board meeting and later targeted with threats and hate speech online.”

Black and minority students walked out of Lowell in 2016 after a poster was found in the school library disparaging Black History Month.

Minority students at the time also complained they had experienced incidents of being called “ghetto” or dirty, of having other students refuse to believe they could be taking Advanced Placement classes and of being told by adults that they needed to change the way they looked to fit in.

“We are committed to finding the perpetrators and ensuring full accountability for this heinous act,” said SFUSD superintendent Dr. Vincent Matthews in a statement. “We are also committed to supporting the school community as it processes this deplorable incident and in its ongoing efforts to eradicate racism and ensure a safe and respectful learning environment for all students.”

Matthews added, “While we do not yet know who is responsible for this act, we do know that racism persists in our community and is harmful to everyone, especially our students of color. Lowell High School and SFUSD are committed to anti-racist leadership and anti-racist instruction and actively integrate anti-racist lessons for staff and students throughout the learning day. Anti-racist practices remain a priority for SFUSD even in distance learning. This is not just an attack on the Lowell community, it is an attack on all of us.”

Lowell principal Dacotah Swett issued a video statement, saying, “My heart specifically goes out to the members of our community who were targeted — our Black and Jewish students. The images and hateful words are part of historic acts of violence that have been committed time and again and I will not tolerate it … This message is to whomever (sic) made these racist and anti-Semitic attacks on our community: I will pursue all means available to me to hold you accountable for your actions. Your words and actions have no place at Lowell. If you are one of our students the full measure of disciplinary action will be taken in accordance with District policies up to and including expulsion. Your actions constitute hate speech and you will be held accountable.”

The San Francisco Chronicle reported that a petition was started Thursday by Lowell math teacher and Black student union co-adviser Elizabeth Statmore that called for a federal investigation into the hacking.

“These are experiences that our students who are most marginalized, who are least represented — especially at Lowell — are experiencing and I think that shift of course needs to begin at the school site,” board president López said.

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KPIX correspondent Andria Borba contributed to this report