Hamilton Police have a message for parents and caregivers, ensure you know where your children are least they find themselves in serious trouble.
The call comes after to aggravated robberies overnight, both involving girls.
Hamilton City Area Commander, Inspector Rob Lindsay, said the first incident happened outside a fast food restaurant on Ward St about 9.30pm.
"Two girls, aged 15 and 17-years-old, beat up an 18-year-old girl and robbed her of her wallet.
"In the second incident three girls, two aged 15 and one 16, armed with a sharpened weapon robbed a male taxi driver of $10 on Norton Rd about 1.30am. The driver did everything right and exited his vehicle at the earliest opportunity, both sets of girls were arrested and they will all be facing aggravated robbery charges in the Hamilton Youth Court today."
Mr Lindsay said last night's incidents were just the latest in a series of serious incidents involving girls.
Other incidents included several arrests of highly intoxicated youths over the weekend, many of them girls, involved in fights and other disorder.
The weekend before several girls were involved in a large scale fight at the Balloons Over Waikato Night Glow event and three girls were arrested for the assault and robbery of another girl on a City bridge.
"Anecdotally we know offending by females is increasing however they've still got a long way to go before their offending levels near those of males.
"Disturbingly however, our Youth Aid section pointed out females appear far more callous. You might have a boy punch another but they could be mates again half an hour later where as some girls have stalked or harassed their victims for weeks or even months before striking."
Mr Lindsay said it wasn't just the young people involved in incidents that faced the attention of authorities, often their parents and caregivers found themselves under some scrutiny.
"The answer in addressing offending by not just girls but youths in general lies with people taking responsibility.
"Parents and guardians have an obligation to the rest of the community to ensure they have control and can account for young people in their care while the rest of the community has a responsibility to report suspicious activity to Police."
Mr Lindsay said it wasn't just about reporting thefts or violent behaviour.
"Offending, be it tagging, assaults or burglary begins somewhere, what we need is for people to make a stand, report kids out of school during the day, either to the school if you recognise their uniform, or to Police.
"That allows us to make an early intervention, not just via enforcement methods but alongside other agencies so we can work at avoiding incidents such as last night's, long before they happen."
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