Two severed human heads that were being used for medical research were shown in a selfie taken by graduate school students and a professor during a workshop at Yale, according to the Associated Press.

The selfie depicted physician Flavio Uribe, an assistant professor and orthodontics program director at UConn Health and a visiting associate at Yale, and several graduate dental school students near two severed heads on tables, face up, the AP reported.

The students and the doctor were wearing surgical masks in the photo, which was taken last June during a symposium at the Yale School of Medicine that focused on dental-related facial deformities, the AP reported.

The AP wrote that it received a copy of the photo from someone who had come across it on a private group chat. But the AP said it was not given permission to publish the photo by the person who took it, who feared reprisal.

Uribe was instructing the students how to place screws in the cadaver heads, when someone took a photo, he told the news service.

“Somebody unfortunately took a photo,” Uribe said. “It was so quick. I wasn’t sure of the surroundings or scenery at that point.”

Christopher Hyers, a spokesman for the University of Connecticut, told the AP that “UConn Health was made aware of the matter at the time it happened and took appropriate internal steps.”

Uribe told the AP that he hadn’t been disciplined by the school.

Thomas Conroy, a spokesman for Yale, said in a statement that although the workshop was not run by Yale and the severed heads had not been donated to the school, Yale is working on increasing its oversight procedures related to the use of cadavers at the school. He also said that the laboratory had signs at its entrances specifying that photography was prohibited.

“The photograph taken at a symposium at Yale was disturbing and an inexcusable deviation from anything Yale would expect to occur,” Conroy said in a statement. “The faculty member who was involved in the training at which the photograph was taken has been informed of Yale’s expectations in this regard.”

The AP said it did not know how the heads had been attained.

Though the use of cadavers is an established part of medical training, the practice has occasionally caused controversy. In 2016, George Washington University suspended its program that accepted donated bodies for its medical school after it lost track of the identities of about 50 cadavers, rendering the process of returning the bodies to families difficult or impossible. In January, a man who officials described as a high-profile body parts dealer was convicted of wire fraud and illegally transporting hazardous materials after prosecutors alleged that he and his wife lied about the condition and health of the body parts they sold.

Lawrence Rizzolo, a surgery professor and director of medical studies at the Yale School of Medicine, told the AP that the selfie photo was “an egregious violation of Yale policy.”

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