Fadel Alkilani stood by a pile of trash bags filled with American flags on a patch of grass at Washington University in St. Louis on the 20th anniversary of the Sept. 11, 2001, terrorist attacks. Another student approached him from behind and videotaped the incident.

The student recording can be heard saying, “What’s up?”

“Who are you?” asked Alkilani, vice president of finance for the student union.

The video, which was later shared on social media, sparked outrage against Alkilani for allegedly vandalizing a College Republicans memorial commemorating the anniversary of the attacks that killed nearly 3,000 people.

“WOW: A student senator @WUSTL was caught on video removing 2,977 American flags from conservative students’ 9/11: Never Forget Project memorial. Despicable,” the Young America’s Foundation, a conservative youth organization, said on Twitter on Saturday.

Alkilani, a senior studying computer science, said he did remove some of the flags from the campus lawn, each of which represented a person killed in one of the country’s deadliest terrorist attacks.

In an earlier statement, Alkilani stated that his intention was never to “steal” or remove the small American flags from the area. Instead, he planned to place the plastic bags on the lawn alongside statistics “explaining the human cost of 9/11 in the last 20 years,” referring to crimes against American Muslims as well as people killed and displaced in countries invaded by the US following the 2001 attacks.

“Any 9/11 memorial that does not confront these facts is not only incomplete, but it also amplifies pro-imperialist sentiment and actively disrespects those who died as a result of American invasion,” Alkilani said in a statement.

“Muslims like me have faced fear, harassment, and Islamophobia from those who unfairly use the victims of 9/11 as a political cudgel,” he added. The university has now launched an investigation into the incident, which its chancellor called “reprehensible” and an attack on the College Republicans’ free speech.

“The removal of the flags hampered individuals’ ability to commemorate the lives lost on 9/11 and process the trauma of that day….” Students have the right to express themselves, but they also have the obligation to respect the expressions of others,” said Chancellor Andrew D. Martin in a statement. Alkilani was not mentioned by name in the statement.

When contacted late Monday, a university spokeswoman referred to the chancellor’s statement but did not respond to questions about whether Alkilani would face disciplinary action.

College Republicans president Nick Rodriguez condemned Alkilani’s actions and demanded that the student union remove Alkilani as a leader for mocking “one of the most somber days in American history.”

“What does it say about a top American institution to be represented by a student leader who has no respect for property, campus traditions, or the remembrance of thousands of lost lives?” Rodriguez asked the college newspaper. The student union issued a statement on Instagram distancing itself from the incident, saying it did not “endorse or condone” Alkilani’s behavior.

“SU was not involved in the planning or execution of Fadel’s protest….” “We mourn with students on our campus and across the country in memory of the 2,977 souls lost in New York City, Washington, DC, and Shanksville, PA in 2001, as well as the thousands of first responders who died from health complications in the years that followed,” the organization said.

Since the incident became public, Alkilani and his family have received numerous “violent” and “Islamophobic” emails, social media messages, and phone calls, according to the news. Alkilani, who was born and raised in the United States, told The Washington Post in an email that some people told him to “go back to your own country,” while others threatened to kill him.

Alkilani’s Instagram and LinkedIn accounts were inactive as of early Tuesday.

In a statement, the student union condemned the “Islamophobic rhetoric and slurs” directed at Alkilani and other Muslim students on campus.