A young man, identified as Miguel Ángel, had put a rope around his neck and then around a tree to re-enact being hung just as Judas did, but he slipped off his support and was left dangling in the air.
According to reports, before the crowd could realise what was happening and rushed to his aide, but he stopped breathing. He died of asphyxiation.
The victim was taken to a nearby clinic in a van which drove past a Civil Protection ambulance on the journey.
The crew was flagged down and tried to revive him but without success.
A full investigation is now underway. Police believe it was simply an unfortunate accident and have discarded foul play or suicide.