Footage has emerged of a group of young girls attempting to punch a McDonald's worker at a restaurant in Lakelands, before one of them spits at the man and storms out of the restaurant.
The incident occurred at the fast-food outlet's restaurant just north of Mandurah.
Shocking mobile phone footage recorded by bystanders shows a teenager verbally abusing the restaurant worker and trying to throw objects at him while a man attempts to restrain her.
The girl then tries to jump over the counter to punch the worker before another girl spits at the man and storms out of the eatery.
A third teenage girl films the incident with her phone.
Footage of the incident was shared on a local Facebook group, prompting hundreds of comments from social media users condemning the incident and praising the worker for "keeping his cool".
"Welcome to Lakelands Maccas where the rats are out, big props to the dude behind the counter staying calm, if you ever want a feed let me know and I'll shout you one," a user wrote.
A McDonald's spokeswoman said the restaurant had provided CCTV footage to police and "encourage them to take appropriate acction against these customers".
"Behaviour like this in our restaurants in completely unacceptable," she said.
"We will continue to take all necessary steps to ensure the safety of our crew."
The incident comes barely two months after an all-girl gang bashed a McDonald's worker and a medical receptionist during a violent rampage in Cockburn.
The girls, aged between 12 and 15, allegedly assaulted eight people at several outlets at the Gateway Shopping Centre.
