Knife possession offences committed by women and girls in England have risen by 73% over five years, police figures show.
The number of offences has increased by at least 10% every year since 2014, according to data obtained by BBC News through Freedom of Information requests.
Last year, there were 1,509 offences by women and girls recorded.
The highest number of possession cases involving women and girls was in London, but some northern England regions have seen such crimes increase at a faster rate.
The London Metropolitan Police recorded a 52% increase over five years, with a total of 916 recorded offences from 2014 to 2018.
In the same period, Merseyside Police saw a 54% rise, to 499 offences, while offences in Greater Manchester doubled, with 95 recorded last year.
South Yorkshire saw an 82% rise over five years, recording 248 offences involving women.
In total, between 2014 and 2018 there were more than 5,800 recorded knife possession crimes involving women.
Data from 38 forces out of 39 in England shows almost a quarter of knife possession offences involved girls under the age of 18, with the youngest aged seven.
Labour MP Sarah Jones, who chairs the chair of the All-Party Parliamentary Group (APPG) on Knife Crime told the BBC’s Radio 4 Today programme that we don’t know a huge amount about the problem.
She said: “On one level these numbers reflect the kind of overall increase in the levels of knife crime homicides, violent crime that we have seen over the last five years.
“Girls are just as susceptible to the impact of the sweeping cuts that we’ve seen to mental health services, to increased school exclusions, to the cuts to youth services so all of those issues and the underlying causes we talk about affect girls just as much as boys.”
She added that one of the reasons we don’t talk as much about girls and knife crime is that we don’t know very much about it.
She said: “Some people like the children’s commissioner have looked at these issues and what they found is there there are large numbers of girls involved in criminal gangs but there are less of them being convicted so we don’t really know what’s going on with them.
“What we suspect is that it is much the same as sexual exploitation, that girls are groomed into gangs through praise, through friendship, through offers of protection, through asking people to run errands.
“The same kind of patterns you see girls being pulled into sexual exploitation apply to criminal networks. They end up carrying knives and getting involved in crime.”
She said girls are less likely to be seen as suspicious and are less likely to be stopped by police.
“If you are a criminal gang, you want younger children, you want girls, you want people who the police are less likely to pick up so they are quite attractive propositions for those gangs.”