LONDON: Klara Balogova was 18, penniless and heavily pregnant when she rode thousands of miles from Slovakia to England to marry a man she had never met.

She knew he did not want her, or her child. He wanted her European identity card. The marriage was arranged so the 23-year-old Pakistani groom could gain the right to live and work in Europe.

Balogova was promised a clean place to stay in Britain and maybe even some money. But she says within days of arrival, she was moved from Manchester to Glasgow in Scotland, where she was kept in an apartment with her future husband. When he wasn't around, his younger brother would stand over her, and her identity documents were taken away.

“He didn't let me out at any time. He told me it was not possible to go out there,” said Balogova, a shy, petite Gypsy woman who spoke reluctantly, never making any eye contact when she was interviewed. “Once a week we went out together. I was never allowed to go alone.”

Each year, dozens of women like Balogova from the poorer corners of eastern Europe are lured to the West for sham marriages.

The men, who authorities say are often Asian or African, pay large sums because they want to live, work or claim benefits more easily in their chosen country and move freely within Europe. The brokers, often organised criminal gangs, take most or all of the profits. And the women sometimes end up trapped in a foreign country with nothing.

This relatively new form of trafficking comes at a time when Britain continues to tighten its borders, and politicians across western Europe are clamouring for tougher curbs to immigration. Illicit marriages to get around these laws are becoming more common, including direct arrangements between grooms and women as well as the sale of brides.

In Britain, one of several countries where the brides show up, the number of women suspected of being trafficked for sham marriages in 2013 doubled from the year before to 45, according to the National Crime Agency. And Europol last year identified this type of crime as an “emerging phenomenon.”

Most brides get paid-for trips to Britain, Ireland, Germany and the Netherlands, and some don't fully realise what they've gotten themselves into until they arrive. Women have been held captive until their marriage papers are signed, abused by their “husband” and his friends, used for sex and drug trafficking or even made to marry more than once, according to European authorities and charities.

“Depending on the case, a woman can be sold for thousands of euros,” said Angelika Molnar, an anti-trafficking specialist at Europol. “I can tell you it is lucrative.”

In Latvia, trafficking for sham marriages is considered so serious that the government is leading a European Commission-funded international program to combat it. Of the 34 trafficking victims lured abroad from the Baltic state recorded last year, 22 were for sham marriages, according to Laisma Stabina, anti-trafficking coordinator at the country's Interior Ministry.

The numbers are still tiny compared to the thousands of cases of fake marriages reported each year to Britain's Home Office, where brides agree to wed for money and are considered accomplices. But officials acknowledge that the trafficking of brides is hard to track.

“I think the problem is much bigger than we realise, because we only see a small percentage of the offences being committed,” said Phil Brewer, head of Scotland Yard's trafficking and kidnap unit. “There is still not a big understanding of the signs.”

To understand why the women do it, you need only go to Balogova's village.

Balogova, like most women trafficked from Slovakia, comes from a destitute Roma, or Gypsy, settlement. It lies on Slovakia's border with Ukraine and Hungary, and is home to about 250 Gypsies, Europe's poorest minority group. Most of the tin huts have no plumbing, the lanes are muddy, the houses are grimy, and the water from a rusty well is contaminated.

Nicholas Ogu, a social worker, says he knows of several others from Balogova's village who were married in Britain. The trade, as he called it, is controlled by a Gypsy gang that recruits the jobless and poorly educated with offers of good earnings abroad. The women become bogus brides or go into prostitution, while the men typically end up in forced labor.

“They lure them, sometimes offer them a flight ticket, sometimes they go by bus or car,” said Ogu. “They arrange the wedding ... when the men got what they need, they get rid of them.”

The perpetrators are groups of Slovak or Czech nationals who live in Britain, while their crime partners do the recruiting back home, according to Miroslav Wlachovsky, Slovakia's ambassador to London. Scotland is a particularly popular destination, he said, likely because its laws allow marriage without parental consent at 16, compared to 18 in the rest of the UK.

“The scheme is almost always the same,” he said. “They tell them they can work here, in restaurants and so on. It's always promises of a better life, or promises of big and fast money.”

Pregnancy is considered a bonus that boosts a groom's chances to stay. In November, police said they uncovered a trafficking ring where a 38-year-old Pakistani groom had paid up to 15,000 pounds (US$22,000) to a gang for a 20-year-old pregnant Slovakian woman. The woman believed she was going to visit her sister, but was met by a man at Luton airport and taken to an apartment instead. She married her “groom” in July, in a ceremony presided over by a self-proclaimed imam in a house in Rochdale, a town near Manchester, police said.

The woman, who is also Gypsy but cannot be named for legal reasons, was regarded as a more “significant commodity” because she came pregnant, according to Rochdale detective inspector James Faulkner. But once the husband had his legal documents, a woman posing as the victim's sister took her to the hospital for an abortion.

The victim, who had a learning disability and spoke no English, did not realise what was going on until an interpreter spoke to her.

“She thought she was going for help as she had abdominal pains,” Faulkner said. “She was absolutely appalled.”

Sometimes the women are lured with promises not of money or jobs, but of love. In one case, a Lithuanian woman met a Pakistani man in Britain after he wooed her for months on Facebook, according to social worker Kristina Misniene. The man claimed persecution in his home country, and even told the woman he loved her.

Then he snatched away her passport, so she felt she had no option but to marry him. She didn't have the money for a return ticket, and she was raped twice by an “uncle” of the groom, Misniene said.

Another woman from Latvia went to Britain because her boyfriend wanted to sell her off as a bogus bride to offset his gambling debts, according to Gita Miruskina, a lawyer with the Latvian non-profit Shelter Safe House. When she changed her mind, she was locked in a room, and her captors cut her arms with scissors.

“It lasted for 10 days and that's when she agreed she would marry,” Miruskina said. “She was under 20 years old.”

What happens to the women after the marriages is not clear. Some find their way to shelters. Others are cut loose when the men get the residency rights they wanted.

Many of the women are also more vulnerable because they may have troubled lives or little mental capacity. Only a handful of such cases have led to convictions, because they cross country borders and the women are often scared or unable to testify. Also, to the frustration of social workers, some are so poor that they would rather be exploited abroad than stay at home.

Balogova, now 22, was to get married after she gave birth in Britain. But hospital authorities grew suspicious about the identity of the child's father. They also discovered that she had no idea how to find her way to her supposed home, just a few blocks away. In the end, the groom was deported before the wedding. Balogova, who was never paid, stayed at a shelter and returned to Slovakia two years ago with the help of social workers. Her baby, a girl called Aisa, was put in social care in Britain, where she remains, because officials believed she would be unable to take care of her child.

Yet Balogova admitted that she would be willing to take her chances in Britain again.

“I didn't want to come back,” she said flatly. “It was a hundred times better for me in England.”