14/05/2017 1:48 PM AEST | Updated 14/05/2017 1:48 PM AEST

Unknown Substance Released In Melbourne Nightclub Overnight

More than fifteen nightclub goers were treated after inhaling a mysterious substance.

9 News
Police are continuing investigations into the cause of the chemical release.

A toxic substance released in a Melbourne nightclub overnight has left at least one person in hospital.

Police were called to the Perseverance Hotel on Brunswick Street, Fitzroy around 1am on Sunday morning following reports of an assault, but instead attended to a medical emergency.

Fifteen people were treated at the scene by paramedics after inhaling the mystery substance.

A 27-year-old man was arrested for assault related charges but he has since been released.

The substance and means of release remain under investigation.