TWO women were arrested last night following an altercation at a Weston service station last week when one person was spat on and racially abused.

A 49-year-old woman from SA and a 47-year-old woman from Charnwood were arrested on December 18 and released to appear in court on January 9.

Police will allege the two women and a man had parked their vehicle at the service station to change a flat tyre around 10.30pm on Thursday. In doing so, they had parked their vehicle near gas cylinders and ventilation outlets for the underground fuel tanks, where one of the alleged offenders lit a cigarette.

As this was a fire/explosive risk, a member of the staff asked the woman smoking to extinguish her cigarette or move away from the area.

Both women are alleged to have then began racially vilifying the two service station staff. One of the victims was spat on and punched during the incident.

The Charnwood woman has been charged with three counts of common assault and one of offensive behaviour, while the SA  woman has been charged with one count of assault and one of offensive behaviour in a public place.

Witnesses are asked to call 1800 333 000, or via act.crimestoppers.com.au