HAMILTON, Ontario — Tanya Nepinak left her west end Winnipeg home in September with only five dollars in her pocket, intending to go to a nearby pizza shop.

Then, her sister said, she “disappeared from the face of the earth.”

“We don’t have answers as regards to what’s happened,” said Shaunna Neufeld, a detective-sergeant at the Winnipeg Police Missing Persons Unit.

Nepinak is one of an estimated 600 missing, presumed murdered, Aboriginal women across Canada in the past 30 years, according to advocates for Native women here. And the numbers keep ticking upward. Since September there has been at least one other young Aboriginal woman reported missing by her family from Winnipeg, another in Regina and another in British Columbia.

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Native women are an especially vulnerable sector of society. They tend to be much poorer than the average Canadian, and many preside over single-parent homes. Many live in remote communities, where hitchhiking can be routine, or in one of Canada’s major urban centers, where some turn to prostitution to support themselves.

Native women’s advocates suggest that Aboriginal women are often perceived to be available for sex — no matter what they do for a living. The result is that Aboriginal women have a 3.5 percent greater chance of being physically attacked by a stranger than other Canadian women, according to Statistics Canada, the national statistics agency.

“Many of our women who are young, beautiful, many had children but were living on the street as prostitutes, they were being attacked and murdered and missing. So this raised an alarm,” said Jeannette Corbiere Lavell, president of the Native Women’s Association of Canada.

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Take, for instance, the many women who have been abducted along Highway 16, a stretch of road in northern British Columbia where isolated communities of First Nations, or Native communities, live. People there have dubbed it the Highway of Tears.

Only recently have there been any arrests, and only in one or two cases.

In 2007, Robert Pickton, a pig farmer from British Columbia’s lower mainland, was convicted of murdering six women working as prostitutes from Vancouver’s notorious Downtown Eastside, though not all were Native women. He was initially accused of killing 27 women, and confessed to as many as 49.

The Native Women’s Association and other advocacy groups have pressed the government to launch a national inquiry. But their efforts have produced few results — due to a lack of political will, the advocates say.

So now, the groups are turning to the United Nations for help, in a move that could be embarrassing for a country that is perceived as a human-rights leader around the world.

Seven years ago, the association secured a $4-million, five-year commitment from the then Liberal federal government to document missing and murdered Aboriginal women’s cases across the country. The program was called Sisters in Spirit.

“We were able to do the research and to document close to 600 missing and/or murdered Aboriginal women — and this was specific names, details, information,” Lavell said.

But in the spring of 2010, the current Conservative government pulled the program’s funding. The government said at the time that it remained committed to funding groups that fight violence against women.

By August, a UN special representative cited the Canadian government’s lack of “substantive progress” on the issue, noting its “failure to investigate, at the national and provincial levels, the hundreds of cases involving Aboriginal women who have gone missing or been murdered.” It also expressed concerns about the government’s failure to determine whether there is a racial dimension to the murders, and what it might do to prevent more attacks in the future.

In a reply the Harper government cited task forces set up at the provincial level, but maintained it wasn’t a federal responsibility to track those cases. However, in October, Rona Ambrose, the minister responsible for the Status of Women in Canada, announced a $10-million dollar strategy to deal with missing Aboriginal women that included a national tip website and a support center for missing persons.

At first, the association and its advocates were optimistic. “We thought well, this is good, there will be a national strategy, a national program to really investigate, to really look at what is happening, and to see why there is no proper strategy on the part of the police to deal with this,” said Lavell.

But when they began to feel that again not enough wasn’t being done, women’s advocates once again looked to the United Nations.

In October, the UN committee established to eliminate discrimination against women said that it would “initiate an inquiry procedure” to look into Canada’s missing Aboriginal women. It did so under a provision for the UN to act when there are indications of “grave or systemic violations” by state parties — suggesting that the Canadian government had neglected to properly pursue these cases.

The committee could then consider a visit to Canada — if the government approved.

The government, in a formal response to the UN, said that it shared the committee’s “concern” about the missing and murdered women. “Governments are addressing the issue through a number of approaches, including the creation of several provincial task forces to investigate cases of missing and murdered women,” it said in a statement.

Still, the progress of the committee is a major step: the only time the UN has requested to visit a country for the purposes of investigating similar crimes was when it asked to go to Mexico to pursue the epidemic of murdered women in Juarez.

“The next question in terms of Canada’s cooperation is, is Canada going to agree to a visit?” said Shelagh Day, a lawyer, and member of the Canadian Feminist Alliance for International Action, a human-rights group that, along with the Native Women’s Association, petitioned the UN for an inquiry.

“I can’t speak hypothetically, but as I said, the committee will decide or not whether they will conduct an inquiry, and should this go ahead it could include a visit if warranted, and if they receive consent from the Canadian government. But it’s way too early to say whether that consent would be given,” said a departmental official for Foreign Affairs in a phone interview with GlobalPost, who declined to be identified.

“There was change for the better in Mexico when the [UN] intervened. And we’re hoping that the same could take place [here], because we as a women’s organization haven’t been able to push the government to agree to something like this ... maybe this will happen now,” Levall said.

The UN could make its decision on whether to launch an inquiry at its next meeting in February.

Meanwhile, back in Winnipeg, Gail Nepinak is still hoping for some information about her sister.

“It’s still early; it’s only been three months,” she said. “If something happened, then she can come home. My mom said if she’s gone, at least let us give her a proper burial. Let us say our goodbyes to her. If someone did something to her, at least give us that, you know?

There has to be at least one person who saw her, somewhere.”

Tanya Nepinak, 31, is five feet two inches tall, weighs 100 pounds, with brown eyes, long brown hair, a red birthmark on the left side of her forehead, and her name T-A-N-Y-A across the fingers of her right hand. Anyone with information is asked to call the Winnipeg Police Missing Persons Unit (204) 986-6250.