A boy allegedly started throwing chocolates at the victim, before a girl pushed her to the ground and punched her, Frankston detective Senior Constable Ryan Collins said. The girl was repeatedly kicked in the face and body while she lay cowering on the ground, before one teen used his cigarette lighter to set her hair alight. "We believe a boy kicked her repeatedly in the face and body while she was on the ground," Senior Constable Collins said. "It is alleged a [boy] then demanded her bag and mobile phone, while another teen used his cigarette lighter to set her hair alight. "The group then ran off with her bag."

The girl managed to run home and was taken to Frankston Hospital with a fractured right hand and serious swelling and bruising to her face. Police have arrested and charged the seven offenders, aged between 12 and 14. Of the alleged offenders, four are 14 years old, two are 13 and one is 12. The 13-year-old boy has been charged with armed robbery, assault and breaching bail. It is understood he has been remanded in custody.

The 12-year-old alleged offender also remains in custody. Senior Constable Collins said the act of setting the girl's hair on fire was "certainly concerning and an aggravating factor" in the case. Frankston Skate Park employee Jake Griffin said he was working at the skate park before the attack on Friday night. He said he saw "some guy" run from the train station up the road and into the skate park, who was then arrested by police. But he said that incident occurred earlier in the evening, around 6pm, and there was no one working at the skate park at 9pm on Friday.

"We open and close it, but you can use it outside of our hours," Mr Griffin said. "There isn't much reason for us to be there after it gets dark." He said the attack was "disgusting". Frankston City Council chief executive Dennis Hovenden said he was "extremely disappointed and concerned" to learn about the violent attack. "This type of alleged behaviour is extremely unwelcome in Frankston and we wish the young girl and her family the best in her recovery," Mr Hovenden said.

He said the park was supervised during the day, which had been effective in improving behaviour and reducing incidents at the park. The council had not seen the need for lighting around the skate bowl itself, Mr Hovenden said. "The skate park is not for use at night and as lighting would encourage more and inappropriate activity, [the] council does not see the need to install lighting for the skate bowl itself," he said. "Lighting, however, is provided in the park along the pathways, which link the fully lit car park to Chisholm Institute. "This level of pedestrian lighting is appropriate for the park and enables passive surveillance from local residents, who overlook the reserve.

Mr Hovenden said the council was discussing the matter further with the YMCA. Anyone with information is asked to contact Crime Stoppers on 1800 333 000.