The investigation was the largest and most complex that Lancashire police had ever undertaken and it ended with 13 people being jailed for a total of 198 years. The highly sophisticated gang, based in Preston, imported guns, drugs and ammunition and had direct links to underworld organisations in Poland, the Netherlands and Scotland.

Four of those convicted were women. But unlike other cases where the females in the gangs play only a small, supporting role, two of the Preston gang – sisters Nyome Hue and Stella Taylor – were key figures, running the enterprise alongside their brother Ivan.

A month earlier, five men and two women were jailed at Manchester crown court for their part in running a multimillion pound cocaine gang. One of the women, Rebecca Edmonds, was simply a courier but the other, Marcee Pepper, had a crucial role. She was described by the judge as the "facilitator and secretary of the gang" and the jury were told that she was in charge of arranging logistics and moving illicit profits around the world.

Law enforcement officials and criminologists have expressed alarm at a disturbing trend where increasing numbers of women are becoming involved in all levels of criminality, from violent confrontations and murders among teenage street gangs to the highest levels of the international drug trade.

Earlier this month, a woman was thrown to the ground and robbed by a gang of four teenage girls as she walked along Bangor High Street. The following week two girls were assaulted by a larger group of girls as they waited at a bus stop in Worcester. Such is the fascination with female crime that production is due to start on a new film, Sket, which will explore the culture of girl gangs in east London.

Although women are still statistically far less likely to be involved in crime than men, that gap is narrowing rapidly. Ministry of Justice figures from 2009 showed that annual arrests of teenage girls and women had reached a record level of more than 250,000. One in four violent attacks now involves a female. Last year, more than half a million assaults were carried out by women or involved a female in a gang.

"In recent years, girls have seen the status and power given to male gang members and decided they want some of that," says clinical psychologist Dr Funke Baffour. "They have low self-esteem and confuse having self-respect with getting respect from others. To get into these gangs often requires people to commit an act of violence, but because there is a hierarchy and a jostling for position, these crimes become increasingly violent."

Last June, the 17-year-old leader and a 16-year-old member of London gang Girls Over Men were jailed for a horrifying attack on a 16-year-old girl. They abducted their victim off the street in Stratford, east London, at knifepoint, stripped her, then beat her with belt buckles for allegedly "disrespecting" the leader's mother. A third member of the gang, Sophia Austin, 18, took mobile phone pictures of the traumatised victim and sent them to friends. Later, the 16-year-oldwas overheard telling inmates at the young offender institution where she was being held that she should have got a male friend to rape her victim.

Youth Justice Board figures show that the number of personal violent attacks by girls dealt with by youth offending teams rose by 48% between 2003 and 2008, from 10,412 to 15,413. They also show sharp increases in the number of public order offences committed by girls under 18 over the same period, up 37% to 5,852, and racially aggravated crimes, up 113% to 758.

Many women and young girls find gang culture exciting. Chloe Goodman could hardly contain her enthusiasm when she was paid £300 to hide a gun for a member of Manchester's Lostock Crew gang. She began chatting to other members online and eventually posted pictures of herself posing with a variety of weapons. Women have long been used to carrying weapons on behalf of male gang members; evidence suggests they are increasingly carrying weapons for their own use.

When 17-year-old Sian Simpson was stabbed to death in Croydon in 2007 it was initially reported that she had been trying to break up a fight between two girls. Later it emerged that her street name was "pitbull" and that she had been stabbed with her own knife during the fight.

Women are also routinely used as "honeytraps". Samantha Joseph was so enamoured of her gang leader boyfriend, Danny McClean, that she agreed to lure her besotted admirer Shakilus Townsend into a trap so that McLean could "fix" him. Townsend died after being beaten with a baseball bat and stabbed six times while Joseph looked on.

When Constance Howarth was arrested at gunpoint in May 1997 and three Mac-10 Ingram submachine guns each capable of firing 1,100 rounds a minute, were found in the boot of her car, she immediately played the "dumb blonde" card. "I'm just a girl," she told the officers. "I don't know anything about guns. I was just running an errand for a boyfriend. He's now disappeared – he is a bit of a rat, the situation he has got me into."

In reality, Howarth had spent almost her entire adult life rubbing shoulders with some of Britain's most notorious criminals. Among her closest associates were Glasgow Mr Big, Paul Ferris, London-based old-time godfather Henry Suttee and Salford underworld figure Paul Massey.

In 2007 she was convicted of a bungled plot to kill a rival gang leader. Her role was to sit in a pub and guide two young men towards their target. In the event, the would-be hitmen were overpowered and killed with their own guns. Howarth went to the bathroom and refreshed her lipstick before leaving the pub. She was eventually jailed for 20 years.

A report by the Institute for Criminal Policy Research suggested that the increase was due to women being more willing to commit and admit offences because society had changed its expectations about their behaviour. Although this may be more apparent within a "ladette" and binge-drinking culture, and the antisocial behaviour associated with it, women are also increasingly involved in crime at a far more sophisticated level.

Once a rite of passage, gang membership for many youths is now the first step in a criminal career. According to Dr Roger Green, director of the centre for community research at Hertfordshire University, once gang members start making money it becomes almost impossible for them to escape the culture.

With organised crime becoming more and more businesslike, those with the best management and logistical skills – whether they are men or women – are the ones who rise to the top. "It's fantastic for women to break glass ceilings. I wish this was one we weren't breaking," said Anne Milgram, attorney general for New Jersey in the US. "It's a disturbing elevation. Women were largely relegated to subordinate roles as girlfriends and gofers. Now they are taking over dominant roles in traditionally male-dominated gangs."

Milgram was speaking last August after the arrest of Iyesha Harrison and Tyesha Stephens, two women running a wholesale and retail business selling heroin, cocaine and marijuana on the streets of Newark, New Jersey, as well as supplying other gangs.

Police estimate that their operation was making $50,000 (£30,000) a week and was affiliated to the Bloods, the notorious Los Angeles street gang which has offshoots across America. While some Bloods gangs have a position called first lady – a woman in charge of enforcing discipline or collecting members' dues – this was the first time a gang had been found to be fully female-led. Police estimated that women make up 10% of gang membership but account for only 1% of leadership positions.

In March, the US Drug Enforcement Administration announced that, of 385 drug smugglers being sought in US border states, 31 were female. Five were described as "armed and dangerous".

Earlier this year, Interpol issued a red-notice arrest warrant for Angie Sanselmente Valencia, a Colombian-born 30-year-old lingerie model who is believed to be the mastermind behind an all-women gang that smuggles cocaine into the UK via Cancún, Mexico. She is the former wife of a Mexican drug lord but struck out on her own after they split up. Her network began to unravel when one of her "drug mules" was caught at Ezeiza airport, Buenos Aires, carrying 55kg of cocaine. The 21-year-old woman began to talk and within 12 hours police investigators had arrested a further three people. The drug mule had made no attempt to hide the cocaine in her suitcase because she had been told no one would stop her at the airport.

Where women have managed to establish themselves in high level criminality, they tend to excel, provided they are prepared to be as ruthless as those around them. Beverley Storr had not only held her own in the male-dominated world of organised crime but had managed to rise to the top. Ruthless and determined, she spent years successfully arranging for large quantities of drugs to be smuggled from Spain into Britain until she was caught in Malaga with one-and-a-half tons of cannabis worth £3m.

After serving her time, she moved to Copenhagen with her long-time lover, Reginald Blythin, a convicted drugs trafficker and former armed robber, and quickly established new contacts that put her back at the centre of a lucrative smuggling enterprise. Storr was then accused of involvement in the murders in Copenhagen of two of her former associates. In the first, expat villain John McCormick was shot dead in the hallway of his home. Less than four weeks later the body of Colombian Arturo Rodríguez Miranda, 54, was pulled from the water at the harbour village of Hou, a popular tourist destination in the Aarhus region of Denmark. Miranda's hands had been tied behind his back and his throat had been cut so deeply that he had almost been decapitated. He had also been shot in the back with a shotgun.

Storr was charged with murder but was eventually released on a technicality with police hoping she would lead them to Blythin who was still at large. Instead, Storr returned to the UK and eventually took her own life. She was only 43.

Gangland by Tony Thompson is published by Hodder & Stoughton at £16.99