But the government is firing back, accusing James Anaya, the UN special rapporteur on the rights of indigenous peoples, of spreading inaccurate information for the sake of publicity.
"Anyone who reads the letter will see it lacks credibility," said Michelle Yao, spokeswoman for Aboriginal Affairs Minister John Duncan.
"Our government is focused on the needs of the residents of Attawapiskat — not publicity stunts."
Native leaders asked Anaya earlier this month to look into living conditions in the James Bay community and elsewhere.
"I have been in communication with the government of Canada to express my deep concern about the dire social and economic condition of the Attawapiskat First Nation, which exemplifies the conditions of many aboriginal communities in the country," Anaya said in the statement issued from Geneva on Tuesday.
He said he wrote to Canadian officials on Monday, expressing his worries and asking them for more information about funding, policies and respect for human rights.
"The social and economic situation of the Attawapiskat (community) seems to represent the condition of many First Nation communities living on reserves throughout Canada, which is allegedly akin to Third World conditions," he writes in a public summary of the letter. The full text was not immediately released.
He notes non-aboriginal people in Canada have some of the best living conditions in the world, but aboriginal people routinely face higher poverty rates and live with poorer health, less education and higher unemployment.
Anaya says he has been told Ottawa systematically underfunds reserves and does not respond adequately to cries for help. He reiterates many complaints raised by the Assembly of First Nations as well as the First Nations Child and Family Caring Society of Canada.
The Caring Society is fighting Ottawa in court, accusing the federal government of discrimination by funding First Nations child welfare, health and education at lower levels than non-aboriginal populations.
Anaya said he wants to hear Ottawa's side of the story and vowed to monitor federal policies and responses very closely.
A spokeswoman in Anaya's office said he has no first-hand knowledge of the Attawapiskat situation.
"Information about the situation came from various sources and is part of Prof. Anaya's general monitoring of the conditions of indigenous peoples around the world," Maia Campbell said in an email.
"As Prof. Anaya has not engaged in a fact-finding investigation about this situation, he is only expressing concern about the information received."
New Democrat MP Charlie Angus, whose riding includes Attawapiskat, invited Anaya visit the little community and see the situation for himself.
"This crisis has been going on for months," Angus said in a news release. "Families will be spending winter in tents in Attawapiskat and the Conservatives just don’t seem to care. Conservative inaction is a disgrace and giving Canada a black eye in front of the world."
The rapporteur is responsible for promoting laws and policies that support indigenous peoples around the world, as well as researching their living conditions and issuing reports and recommendations.
He has no binding authority. Rather, he aims to shame governments into action by bringing unacceptable conditions to light.
"It is enormously embarrassing, diplomatically, to be criticized by the UN on such issues," said lawyer Paul Champ, who represents the Caring Society.
"Canada has a history of avoiding international scrutiny of its treatment of First Nations peoples."
But officials in the minister's office said the letter from Anaya was riddled with inaccuracies, including being addressed to the former minister of foreign affairs, Lawrence Cannon.
"We will correct the inaccuracies in this letter, beginning with the fact that the special rapporteur could not name Canada's minister of foreign affairs," Yao said in an email.
Cannon was defeated in the election last May and was replaced as foreign minister by John Baird.
The Attawapiskat First Nation declared an emergency in October because 25 families were living in housing too flimsy to face the harsh winter.
In response, the Red Cross raised $300,000 from Canadian donors and flew in emergency supplies for families in the most precarious conditions.
Federal and provincial emergency officials are refitting a local healing centre as a temporary shelter for the winter. And the federal government has purchased 22 new modular houses, with the hope that they'll be in place later this winter.
At the same time, however, Prime Minister Stephen Harper has accused the band of mismanaging federal money and not producing adequate results for the $90 million transferred to the community over five years.
He has ordered a full audit and placed administration of the band's finances in the hands of a third-party manager — a decision that angered band leaders and sparked a legal fight.
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