Police have revealed details of a wild rampage in Cockburn, saying the young girls involved acted as a pack.

Eight people were assaulted during the violent spree, including a McDonald's worker who may have a broken nose.

Police say the girls responsible for the assaults are aged just 12 to 15.

The seven children got off the train at Cockburn about 5pm yesterday and started assaulting strangers as they walked towards Cockburn Central shopping precinct.

Camera Icon Sergeant Dave Eaton says the girls acted in a pack as they confronted strangers in the street. Credit: 7News.

They ended up inside McDonald’s outlet where police say they tried to steal a till.

The 45-minute rampage left people so scared, they ran and hid in a nearby medical centre.

Sergeant Dave Eaton says the girls confronted people in the street.

"Their behaviour was extremely aggressive as they were walking down the streets towards other people," he said.

"There was, if you don't want to describe it as that, but a pack mentality."

Two girls have been charged with stealing an iPhone and a necklace.

Police have appealed to anyone who filmed or took pictures of the rampage to contact Crime Stoppers.