Authorities in Italy are trying to figure out the bizarre mystery of an actor who was strangled on stage in Pisa – during a hanging scene.

Pisa University Hospital says doctors declared 27-year-old Raphael Schumacher clinically dead late Thursday – five days after the incident – which he never recovered from. News reports said a medical school graduate who was in the audience sounded the alarm – after noticing the actor was in real distress – while enacting a hanging.

The theatre directors say the piece, about an adolescent’s existential crisis – was supposed to end with a fake pistol shot – but Schumacher changed it without informing them.

Prosecutors are investigating whether a lapse in safety procedure was to blame – with the focus on a possible stage accident – rather than suicide.

Schumacher’s family and friends have refuted suggestions the actor intended to take his own life.