Shannon Alexander and her teenage friend Maisy Odjick had planned to go to a dance one Saturday night in September of 2008, then sleep alone at Shannon's house on the Kitigan Zibi Anishinabeg First Nation in western Quebec.

On Sunday, Maisy's grandmother and mother could not reach her by phone and started to worry. On Monday, they went to the Alexander home, where they found the girls' purses, identification and backpacks. But Maisy, 16, and Shannon, 17, were gone. More than four years later, there is still no sign of them.

Maisy and Shannon are just two of some 600 aboriginal girls and women who have been documented as murdered or missing over the past two decades. First nations researchers say there are many more who have vanished without a trace, but whose cases have not generated paperwork or police interest.

Story continues below advertisement

Faced with what they say is a critical situation that is being ignored outside their own communities, the chiefs of the Assembly of First Nations passed a resolution this week demanding that the government of Canada establish an independent public commission to investigate the disappearances and killings of aboriginal women.

The chiefs, who met for three days in Gatineau, want AFN National Chief Shawn Atleo to work with the provinces and territories to press for such an inquiry and for a national strategy to be developed to stop the violence being inflicted on their daughters, mothers, aunts and sisters.

If the Conservative government of Prime Minister Stephen Harper ignores their demands – as it has twice – they plan to take the fight to Parliament Hill as well as police stations and the offices of federal and provincial politicians across the country.

"Over four years later and a lot of questions still remaining," Gilbert Whiteduck, the chief of the first nation where Maisy and Shannon went missing, said Thursday after a session to discuss the threats faced by native women. "It's like they were taken off the face of the Earth. It's like they disappeared into nowhere."

The provincial police in Quebec and the first nation's own force have followed every lead to no avail. But some participants at the AFN meeting said law enforcement officials too often refuse to take reports of missing native women seriously – that victims are dismissed as runaways.

And they noted, on the day that serves as an annual memorial for 14 women who were gunned down 23 years ago at the École Polytechnique in Montreal, that there is little notice or attention given to the many first nations women who are killed every year with guns and knives.

According to the Native Women's Association of Canada (NWAC), about 50 per cent of the violent deaths of aboriginal women and girls result in homicide charges – compared with 76 per cent for the general population in 2011, according to Statistics Canada.

Story continues below advertisement

In British Columbia, at least 18 women have vanished or been killed since the 1970s near the Yellowhead Highway, known as the Highway of Tears, which runs from Manitoba to the Pacific Ocean.

Mr. Atleo and others say a public inquiry would draw attention to these issues and give people who have lost a female relative or friend to violence a chance to tell their stories.

NWAC president Michèle Audette has been fighting for years for a public forum to examine the deaths and disappearances of indigenous women.

"My dream, and the dream of NWAC, of course, is that it will change legislation, policy, programs," Ms. Audette said, "and it will give an overview of the root cause of this systemic discrimination and how come women are ending like this with no answers and no justice."