Italian actor Raphael Schumacher was declared clinically dead on Thursday, days after accidentally strangling himself during the performance of a play in Pisa.

The 27-year-old performer had been in a coma since Saturday, when a hanging scene in the experimental production “Mirages” at the Teatro Lux went horribly wrong, according to CNN.

A medical student observing the performance noticed that Schumacher was trembling during the hanging scene and intervened, removing the mask from his face and loosening the noose around his neck. He was taken to a local hospital.

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On Thursday, Pisa Today reported that doctors had declared him clinically dead since he was not responding to treatment.

“We are shocked,” Gabriele De Luca, the theater’s art director, told the Daily Mail. “No one, not even us, understands how this happened.” However, De Luca also told the Italian newspaper Il Giorno that Schumacher had altered the script to replace fake gunshots with the noose.

Local authorities have launched an investigation into the incident to ensure that proper safety precautions were followed.

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The performance involved spectators walking around scenes in different parts of the theater, including the courtyard, where Schumacher’s hanging scene took place.