Police keep protesters from pushing through a door, before a debate for Louisiana candidates for the U.S. Senate, at Dillard University in New Orleans on Wednesday.
CNN  — 

Protesters clashed with police outside a US Senate candidate debate Wednesday in Louisiana that included former Ku Klux Klan leader David Duke.

Police used pepper spray on protesters as they tried to squeeze through the doors of the debate venue on the New Orleans campus of historically black Dillard University, according to a university spokesman.

“I can taste the pepper spray,” Nick Reimann, a writer for Loyola University’s student newspaper, tweeted.

Six people, including one student, were arrested for obstructing traffic, the spokesman said.

Outside, protesters carried signs decorated with swastikas declaring “No hate,” and “We have not forgotten.”

Dillard student group, Socially Engaged Dillard University Students, had vowed to protest the debate after the school denied its request to exclude Duke.

“His presence on our campus is not welcome, and overtly subjects the entire student body to safety risks and social ridicule,” SEDUS representatives wrote in an open letter, according to CNN affiliate WGNO.

While spectators were banned from the debate, outside students chanted: “No Duke. No K-K-K, no fascist USA,” and tried to force their way into the auditorium, the Times-Picayune reported.

Raycom released a statement before the debate saying that the contest would be “conducted on a closed set,” per their rules. Journalists were allowed to watch from a separate room and it was broadcast live locally.

Inside the debate hall, Duke, who has supported Donald Trump’s campaign for president, was calling the demonstrators “Black Lives Matter radicals.”

Trump has disavowed Duke’s support.

In his closing argument, Duke said: “The Black Lives Matter movement calls for the murder of police officers and calls for the death of police.” He offered himself as a counter to this sentiment: a candidate who would “defend the police” and fight for white people, who “also deserve human rights.”

Duke also took aim at Jews, when he was asked by moderator John Snell why he referred to those reporting on the tape of Donald Trump boasting about sexual assault as “CNN Jews.”

“I’m curious what in world that has to do – that fact that they were Jewish – with Donald Trump and an open microphone?” Snell asked.

Duke said there needed to be more of an open discussion about “any subject,” even sensitive ones.

“There is a problem in America with a very strong powerful tribal group that dominates our media and dominates our international banking,” he said. “I’m not opposed to all Jews. I think there’s a lot of great Jews.”

Duke qualified for the debate by scoring 5.1% in the poll commissioned by the debate sponsor, Raycom, just making the cutoff of 5%. While he is running as a Republican, none of the other five candidates on stage had nice words to say about the former Klan member.

“Somehow, this snake slithered out of the swamp,” said Democratic Candidate Caroline Frayard about Duke’s presence.

As the race stands, Duke’s chances seem non-existent. The same Raycom poll released on October 20 that showed Duke at 5.1% had Republican State Treasurer John Kennedy ahead with 24 points, followed by Democrat Public Service Commissioner Foster Campbell.

This story has been updated.

CNN’s Emanuella Grinberg and Tony Marco contributed to this report.