The Walker Art Center’s executive director expressed regret Friday to Minnesota’s American Indian communities over tensions raised by a new sculpture, “Scaffold,” a gallows-inspired work based in part on the hanging of 38 Dakota tribe members in Mankato in 1862.

It will debut at the Minneapolis Sculpture Garden June 3.

“I should have engaged leaders in the Dakota and broader Native communities in advance of the work’s siting, and I apologize for any pain and disappointment that the sculpture might elicit,” Olga Viso wrote in an open letter to The Circle, a Twin Cities newspaper that serves the American Indian community.

The letter was posted Friday afternoon on the Walker’s website.

Several protesters gathered Friday outside the garden, which is still under construction. Signs posted on the chain-link fence read: “Not Your Story” and “Hate Crime.”

“It’s five generations ago, and really we have to realize that 1862 was not that long ago,” said Sasha Houston Brown, who is Dakota. “I think it should publicly be taken down so we can see it come down. It’s really traumatizing for our people to look at that and have it just appear without any warning or idea that they were doing this. And it’s not art to us.”

Graci Horne, an artist who is Sisseton Wahpeton Dakota/Hunkpapa Dakota, was dropping thick red paint onto magazine pages, then slathering it onto a sign that described “Scaffold’s” artist, Sam Durant, as a “cultural genocide opportunist.”

Horne said one of her maternal relatives was sent to prison for life in Sioux City, Iowa, along with the warriors who were not executed, and on her father’s side, a relative was hung.

“Scaffold,” by Durant, of Los Angeles, is one of 18 new additions to the garden.

It looks like a viewing station or a wooden jungle gym, but the design is actually a composite of the gallows used in seven U.S. government-sanctioned executions, from the 1859 hanging of abolitionist John Brown to the 2006 execution of former Iraqi President Saddam Hussein.

The hanging of the “Dakota 38” after the U.S.-Dakota War in Minnesota, was the largest mass execution in U.S. history.

“We recognize the decision to exhibit this work might cause some to question the Walker’s sensitivity to Native audiences and audiences in Minnesota more familiar with this dark history,” Viso wrote.

Durant could not be reached for comment Friday, but in a video discussing the work for the Scottish sculpture park Jupiter Artland, he said, “It’s been really exciting and interesting to see how effective and interesting it is in generating conversations.”

He said the piece touches “on a really important aspect of U.S. history that we don’t like to acknowledge, which is the history of lynching. ... You don’t usually get to stand on top of an artwork and have a conversation.”

Viso said she first encountered “Scaffold” in a sculpture park in Europe five years ago. “I saw a potent artistic statement about the ethics of capital punishment,” she said. “Most importantly, I recognized its capacity to address the buried histories of violence in this country, in particular raising needed awareness among white audiences. I knew this could be a difficult artwork on many levels. ... Yet despite my and the Walker’s earnest intent to raise understanding and increase awareness of this and other histories in our American democracy, the work remains problematic in our community in ways that we did not sufficiently anticipate or imagine.”

Viso said she hopes the moment “will foster critical and productive conversations around the complex questions the artist brings forth” and help the Walker be “a more sensitive and inclusive institution.”

The center’s next steps “will be decided in consultation with community members who elect to be involved in this process,” she said. “We recognize that our work moving forward must be done with the guidance of the Dakota community.”

Horne said Viso should meet with elders Chief Arvol Looking Horse, Paula Horne, Belinda Jo Pretty Sounding Flute, Nancy Smith, Melvin Lee Brown and Faith Spotted Eagle.

“We were not consulted in the first place, and we want our true representation to come from the elders who have the stories,” Horne said. “The irony is that they have been talking about this their whole lives and nobody listened to them.”

Horne said there will be another protest action at the Walker on Memorial Day, as well as a boycott of the Walker on June 2, the night before the opening.