Panel designed to offer ways for GOP to connect with minority voters falls apart after provocative remarks from attendee

A discussion about race descended into chaos at CPAC on Friday when an attendee suggested slaves benefited from being given "food and shelter".

The provocatively titled session, "Trump the Race Card: Are You Sick and Tired of Being Called a Racist and You Know You're Not One", had been billed as offering a way for Republicans to counter suggestions of racism and win over minority voters.

But it fell apart when two people at CPAC, the largest annual gathering of US conservatives, interjected from the floor and and made a series of extreme remarks.

The session's moderator, K Carl Smith, described himself as a "Frederick Douglass Republican", an audience member interjected. "When Douglass came through slavery … he [wrote] a letter to his former slave master and said: 'I forgive you for all the things you did to me'," Smith said.

From the floor, Scott Terry, pictured, asked: "For giving him shelter and food for all those years?"

Scott Terry, CPAC Photograph: Adam Gabbatt

The comment drew gasps from the crowd, and Smith moved quickly to try and defuse the situation, using a microphone to drown out the protests of another audience member. The controversy overshadowed the rest of the session, a breakout panel from the main conference. At one point, Smith initially refusing to take a question from a young black woman who objected to Terry's remarks.

After the session, Terry, 30, claimed to the Guardian that he was a direct descendant of former confederate president Jefferson Davis, and that he was "not prepared to throw all my ancestors under the bus".

Asked if he disagreed with slavery, Terry described it as a "complicated issue. I can't make one broad statement that categorically it was evil all the time because that's not true". Asked to clarify his comments about "shelter and food", Terry said: "The slaves couldn't just work without being supplied quarters and all that. And you couldn't just … it's not legal to murder a slave. Slaves even had rights under the old south."

Terry was accompanied by Matthew Heimbach, 21, who decried Martin Luther King as a "Marxist". Heimbach is the president of the White Students Union at Towson University in Maryland, a white nationalist group that has been the source of numerous controversies.

When the chairman made a reference to King, Heimbach shouted from the floor that King was a "Marxist" and said that CPAC was "Surrender Con" because it never supported running a true white conservative as a presidential candidate. "We are losing. We keep running moderate candidates."

Heimbach said after the session that the Republican party should focus on attracting more white votes and abandon attempts to reach out to minorities, whom he described as being naturally inclined to vote for socialists and Marxist leaders. "It is the only way we can be successful," he explained.

Heimbach, who was wearing a T-shirt with a confederate flag on the back, added: "If Mitt Romney had won 3% more of the white vote he would have won."

He added that was a fan of Russia for encouraging white people to have a high birth rate. "I like what President Vladimir Putin is doing."