The boy told doctors before he passed that he went to a chemist, mixed the butterfly with water and injected it into his right leg.

Davi Nunes Moreira went into septic shock after he began vomiting and limping following the injection.

He was rushed to a hospital in Planalto in the north-east of Brazil but was transferred to a different hospital in Vitoria da Conquista after his condition began to worsen. He tragically passed away last Wednesday.

A police investigation is looking into the possibility that Davi did this as part of a social media challenge, despite the 14-year-old denying this when asked before he passed.

His death is being linked to potential toxins that could be found in the butterfly mix, which may have caused his body to shut down.

The investigation is being led by civil police in Vitoria da Conquista.

A spokesperson for the police said: "The autopsy results will help clarify the cause of death. The investigation is designed to clear up what happened.”

Davi's father found the syringe that he used under his son's pillow while cleaning Davi's bedroom.

Director of Sao Paulo University’s Zoology Museum and butterfly specialist, Professor Marcelo Duarte said: "Butterflies have a complex biology, and the fluids present in their bodies have not been studied in depth in terms of their toxicity to humans.”