When the Zeitz Museum of Contemporary African Art opened in Cape Town last September, it was hailed as “Africa’s answer to the Tate Modern.” Now, its executive director and chief curator Mark Coetzee has resigned from his post amid an investigation into his “professional conduct,” according to the institution’s trustees.

News of Coetzee’s departure was broken by South African contemporary visual arts publication ArtThrob, which cited “questionable institutional and curatorial practices” at the institution, as well as “unconfirmed rumors for some months that abuses of power were taking place, the nature of which are not known.”

In an email to artnet News, a museum representative confirmed that Coetzee was suspended from his duties on May 16. “An inquiry into Mr. Coetzee’s professional conduct has been initiated by the trustees—Mr. Coetzee has since tendered his resignation,” the spokesperson wrote.

The Zeitz Museum, the world’s largest dedicated to contemporary African art, was founded by German entrepreneur and former Puma CEO Jochen Zeitz. Its founding collection, featuring work by artists including Nandipha Mntambo‚ Mohau Modisakeng‚ Athi-Patra Ruga‚ and Jody Paulsen‚ is on lifetime loan from the museum’s namesake.

Mark Coetzee. Photo courtesy of the Zeitz Museum of Contemporary African Art.

The institution’s Thomas Heatherwick-designed building opened last year to largely positive reviews from critics—but also some controversy surrounding the museum’s link to local real estate corporations and concerns about its white leadership in the former land of Apartheid.

Coetzee was tapped to lead the Zeitz Museum in 2013, after having worked as program director of PumaVision and chief curator of Puma.Creative. Before leading the athletic brand’s art initiatives, Coetzee had been director of the Rubell Family Collection in Miami and an adjunct curator of Palm Springs Art Museum.

Azu Nwagbogu. Photo courtesy of the Zeitz Museum of Contemporary African Art.

Coetzee declined to answer specific inquiries about his conduct from ArtThrob, but told the publication in an email that its questions “seemed quite far removed from the reality of how the museum functions.” He did not respond to artnet News’s request for further comment.

Following Coetzee’s departure, Azu Nwagbogu, the curator-at-large for the museum’s Roger Ballen Foundation Centre for Photography, will serve as executive director and chief curator. A native of Lagos, Nigeria, where he is currently based, Nwagbogu also serves as director of the African Artists’ Foundation in Lagos; the director of the international photo festival LagosPhoto, which he founded in 2010; and director of the online art journal Art Base Africa.

UPDATE, May 21: The City Press is now reporting that junior curators at the museum presented evidence to the board that Coetzee had acted abusively and inappropriately. According to the Press, Coetzee arrived to work Tuesday only to discover his access card had been deactivated. He allegedly resigned at an emergency board meeting that Zeitz flew to the country specifically to attend.

The museum has not commented on whether Coetzee’s resignation is connected to sexual misconduct. In a statement, the museum’s trustees told artnet News: “Given the nature of the inquiry and the process to be followed which is prescribed by SA labor law, we believe that it would be inappropriate for us to provide further details or comment on rumor or speculation.”

A previous version of this article mentioned that some commentators had expressed concerns ahead of the museum’s opening about its ties to private individuals and corporations, including the Cape Town-based Scheryn Art Collection. However, this appears not to have been the motivation for Coetzee’s departure.