Former employees of the Smithsonian’s National Museum of African Art claim high-level staff created a racist work environment.

Ten former staff and board members of the Smithsonian National Museum of African Art (NMAfA) in Washington, D.C. have accused the institution of harboring a “culture of racism” in an open letter addressed to Smithsonian secretary Lonnie G. Bunch III, according to Huffington Post.

The letter calls for the resignation of NMAfA’s deputy director and chief curator Christine Mullen Kreamer, who the signatories accuse of cultivating and continuing a legacy of institutional racism that stretches back years. The letter alleges that Kreamer favored white employees for promotion, and has been the subject of “multiple complaints” concerning bullying, hostility, and mismanagement. The letter also claims former director Gus Casely-Hayford, who held the position from 2018 to 2020, also contributed to a hostile work environment, firing two senior-level Black staffers between 2019 and 2020 without any evidence of underperformance.

The signatories claim that more than 10 former or current Black employees have experienced or reported “incidents of racial bias, hostile verbal attacks, retaliation, terminations, microaggressions, and degrading comments,” only to be ignored by high-level staff. One former employee claims that only five full-time Black employees remained at the museum by the time they left.

In response to the letter, Bunch told the New York Times:

This is professional and personal—this is really important to me. What I will do is evaluate this, look into this, put my own fingerprints on it, understand exactly what’s gone on and try to get to the bottom of it. There is no room for racism at the Smithsonian. Too many times, I was the only Black person in the room and I want to make sure that doesn’t happen anymore.