Mystery gas affects 15 people on Melbourne hotel dancefloor

Fifteen people have been affected by an “unknown substance” that police believe was discharged on the dancefloor of a Melbourne hotel.

Police were called to reports of an assault at the hotel on Brunswick Street in Fitzroy at 1am, but arrived to find people suffering from the effects of the mysterious substance.

Paramedics treated a number of people at the scene, and police have launched an investigation.

A 27-year-old man was arrested at the hotel over the alleged assault, but has been released pending summons.

Anyone with information is urged to contact Crime Stoppers on 1800 333 000.