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Staff members dismantle the lectern after a news conference held by Alberta Premier Danielle Smith in May. The provincial government issued a revised statement in celebration of Alberta’s birthday that removed reference to Indigenous peoples.Jeff McIntosh/The Canadian Press

The Alberta government released a statement celebrating the province’s birthday on Tuesday, but an hour later, a revised version was sent out that removed any reference to Indigenous peoples.

The misstep unfolded at a time when relations between the government and the First Nations in Alberta have been strained over the coming referendum on Oct. 19.

Several First Nations have said that any vote on whether Alberta should separate from Canada is a violation of treaty rights.

Shortly after 10 a.m. local time on Tuesday, the government published a statement on behalf of Premier Danielle Smith commemorating the day Alberta joined Confederation in 1905 and became a province of Canada.

The third paragraph of the first statement read: “We recognize the Indigenous Peoples whose enduring connection to and stewardship of this land continues to shape Alberta. Over generations, people from many backgrounds have strengthened our communities through hard work, innovation, entrepreneurship, and a shared belief in opportunity.”

But an hour after it came out, the province sent an edited, expanded statement that removed any reference to Indigenous peoples from the English-language statement.

“Generations of Albertans from many backgrounds have helped build our province through hard work, innovation and a shared belief in freedom. Their legacy can be seen in the strong communities, thriving industries and quality of life we enjoy today,” Ms. Smith’s new statement read.

The original French-language statement mentioning Indigenous peoples was not revised in the second release.

Yonathan Sumamo, a government spokesperson, said the revised version was “issued in error” and the original, which mentioned First Nations, “stands.”

“We apologize for this error and any confusion that it may have caused,” Mr. Sumamo said in an e-mailed statement.

Ms. Smith, at an unrelated news conference, blamed Alberta’s public service for the revision.

“The public service posted one statement and then took it down and put up another one. I said, ‘Why didn’t you put up the original one?’ And so I’m not exactly sure what happened with that glitch,” Ms. Smith said, adding that Indigenous communities are one of many groups that have “helped build the province.”

Trevor Mercredi, the Grand Chief of Treaty 8 First Nations, called the change made to the Premier’s statement “deeply troubling.”

“Treaty 8 Sovereign First Nations and all First Nations across Alberta have always been part of the history, present and future of this province. Our Nations are not a footnote to Alberta’s story,” Mr. Mercredi said in a statement. “Treaty Nations were here long before Alberta existed, and our place in this land cannot be erased when it becomes politically inconvenient.”

He went on to say that the omission was concerning given the Oct. 19 referendum, which he says challenges “the constitutional status of Treaty rights and the duty to consult.”

“Respect for First Nations must be reflected in the government’s words, actions and relationships,” Mr. Mercredi said.

The revised statement remains on Ms. Smith’s social-media accounts on X and Instagram.