The man had several broken ribs as well as fatal head injuries consistent with blows from a stick or a river stone.

He had taken part in an Amazonian spiritual shamanistic rite featuring the consumption of the powerful psychedelic ayahuasca, whose use is becoming increasingly popular among hipsters worldwide, an autopsy found.

Alex Marangon, from Marcon near Venice, was initially thought to have fallen in the river near Treviso and hit his head.

Marangon’s family lawyer, Nicodemo Gentile, told ANSA Saturday that the young man had been “struck by several people” and that “many people know what happened but are not telling”.

About 20 people are said to have taken part in the rite, part of a spiritual retreat.

Now, however, the possible murder weapon has not yet been found.   

ANSA