Update 11/5/15: This article has been updated to reflect the conclusion of an investigation by Berkeley High School administrators, which identified the student responsible for the image.

On Thursday morning, more than 2,000 Berkeley High School students and teachers staged a march through the streets of Berkeley to protest after the discovery of a hostile image posted on a school computer the day before.

In a scene reminiscent of the high school’s December Black Lives Matter walkout, demonstrators streamed through UC Berkeley’s Sproul Plaza about noon after beginning at Berkeley High and later chanting outside of City Hall. Their actions came in the wake of news that an image containing threatening language toward black individuals was discovered on a school library computer Wednesday.

“Last year, we were marching for a cause and an idea, but today, we were marching against a specific incident, with a specific sense of action and for a specific set of needs to be met,” said Alecia Harger, the school’s Black Student Union co-president, who helped lead the demonstration. “We had to retrace those steps because so little has changed despite how much we fought last year.”

On campus, protesters chanted, “You’re the ones that showed us how. UC Berkeley join us now,” imploring campus students to join the march.

“Legislation, all that stuff, it helps. But this, what we’re doing here, is all we got left,” said Berkeley High student Damani McNeil. “We are unified — we know it’s time for change.”

Late Wednesday night, Berkeley High Principal Sam Pasarow notified students and parents via email that the administration was investigating an incident he called a “hate crime.” 

On Thursday afternoon, high school officials concluded the investigation after a student sent forward a statement to administrators confessing to the actions. The administration is now considering what disciplinary action will follow and has turned over evidence to Berkeley police, who will determine if there is any criminal charge. The student’s name will be kept confidential.

The protest originally began as a walkout Thursday morning, when about a thousand students flooded the school’s courtyard about 9 a.m., outside the library where the image was discovered.

Roughly thirty minutes later, Pasarow and school district superintendent Donald Evans emerged to share words with the crowd of students, condemning the act. After they spoke, Harger and BSU co-president Nebe Zekaryas made a spontaneous decision to leave campus and move to the streets.

‘“When I came to school, I was angry, and I’m still angry — and those are the emotions motivating us,” Harger said. “There was frustration and pent-up emotion; we had so much energy that it had to go somewhere.”

The crowd continued to swell as demonstrators circled around the southern perimeter of the campus and began their trek toward UC Berkeley. Berkeley Police Department redirected traffic on several streets in the Downtown Berkeley area while protesters marched through. All streets have since been reopened to traffic.

Just after noon, a crowd of several hundred protesters  — mostly composed of BHS students — made a final stop at the foot of the Campanile, chanting “we have nothing to lose but our chains,” before dispersing to return to classes.  An email sent at about noon to students and parents clarified that classes would not be cancelled that day.

The protest remained peaceful from its inception in the school’s courtyard to its movement into city streets and finally onto campus, where UCPD Operations Division Captain Alex Yao said campus police did not intervene but followed to make sure people’s rights were protected.

Thursday’s march was prompted after a parent volunteer in the high school’s library found an image displayed on a computer screen, resembling the library website’s homepage, that read “KKK Forever Public Lynching December 9th 2015” and also contained racial epithets and hostile language regarding black individuals.

The image jolted the campus community, with many students taking to social media to express revulsion and fear at the image and its implied threat.

When there is a date set for a public lynching, lives are 100% at stake. https://t.co/tgb7Opavig

— SocialJusticeFlower (@anthoknees) November 5, 2015

This is a direct threat to lynch a Black person. Remember Dylan Roof was one of these online racists. Look what he did.

— Brotha B (@BlakeDontCrack) November 5, 2015

Disgusting, devastating, intolerable https://t.co/m7YbzylLpL

— louisa (@louisamyshoe) November 5, 2015

The scale of Thursday’s demonstrations was in large part due to what Harger called “the severity and the singularity” of Wednesday’s incident, which left many students fearing for their safety.  

Student marchers expressed anger that Berkeley High administrators did not notify students of the incident until late Wednesday night, even though the image was found early Wednesday afternoon.  

“What I want is to make sure people don’t look at this as trolling or some joke, but that this is serious — administration needs to do something,” said BHS senior and BSU member Dante Ryan. “All (the email) said was that we are taking this very seriously. I need the administration to do more than just an email.”

The campus’ Black Student Union has in the past expressed criticism with the high school’s communication with students in the aftermath of similar incidents, such as when a noose was discovered hanging from a tree on campus and the campus community was not informed for several days.

School district spokesperson Mark Coplan said that in these situations, the administration focuses primarily on investigating and “does not necessarily want to highlight the efforts of the horrific people who would perpetuate the crime.”

“We’re not going to share that image — that doesn’t help anybody other than whoever put it on the screen,” Coplan said. “We wouldn’t have given the person the mileage of the horrific thing they had done.”

One individual’s action, he added, does not destroy the ongoing work the district has been doing to create a more inclusive space in Berkeley schools.

Part of that work will include giving back Dec. 9 — the date referenced by the poster’s lynching threat — to the school’s black students, creating a space for them “to regain their power and take back the day,” Coplan said.

With a microphone in hand amplifying his voice, McNeil shared similar sentiments of the community’s resilience to those on Sproul Plaza — the massive turnout, he said, was a telling response to the one person who attempted to threaten the black community.

“This was one person, with one computer, who did one thing,” McNeil said. “And look at everyone who turned out here — we’ve got nothing to be afraid of.”

For complete updates of the protest as it unfolded, read the Storify coverage — which features tweets from reporters from the field — below.

Senior staff writers Alex Barreira and Alexandra Yoon-Hendricks, and staff writers Brenna Smith and Anderson Lanham contributed to this report.