A video circulating on social media showed a girl of about 12-14 years-old receiving multiple kicks and punches to her head and body near Splash Palace over the weekend.
Invercargill police have appealed to the public to help identify the victim, and said there were two female offenders involved, both also aged about 12-14.
Community Constable Reuben Boniface said the victim was attacked in a "couple of different places" around Splash Palace.
These included the Southland Girls' High School field.
After feedback from the community, police were able to identify the victim, who sent a statement of complaint.
"She [has been] traumatised with the incident. However, she is coping well," Const Boniface said.
He said police would continue to investigate the incident. The matter has been referred to the Youth Court.
"We are following strong lines of inquiry to hold these offenders to account. We would like to thank members of the public for the information provided and remind those involved that this behaviour will not be tolerated."
