A new federal report has revealed that at least 973 Indigenous children died while attending boarding schools run or supported by the U.S. government. The report, published on Tuesday and commissioned by Interior Secretary Deb Haaland, has prompted calls for an official apology for the pain caused by these abusive institutions.

The report identified several marked and unmarked graves at 65 of the more than 400 American boarding schools established throughout the country. While the report does not specify the cause of death for each child, it lists causes such as illnesses, accidents, and abuse over a 150-year period that ended in 1969.

The boarding schools were created with the intent to forcibly assimilate Indigenous children into white society. Survivors have described the intergenerational trauma that their families and communities continue to experience as a result of these institutions. Children were often prohibited from speaking their native languages and were separated from their siblings, with many facing physical, sexual, and psychological abuse.

Deb Haaland, the first Indigenous person to lead the U.S. Department of the Interior, stated that the investigation aimed to “provide an accurate and honest picture” of what occurred. “The federal government—facilitated by the department I lead—took deliberate and strategic actions through federal policies for Indian boarding schools to isolate children from their families, deny them their identities, and steal the languages, cultures, and connections that are fundamental to Indigenous peoples,” she said in a statement.

Indigenous community leaders in the U.S. and Canada, which also had similar institutional systems, have urged authorities to fund investigations into the unmarked graves at the former schools. The discovery of hundreds of suspected burial sites in British Columbia, Canada, in 2021 led to national recognition and prompted several communities to search for the remains of children who never returned home.

From the late 1800s to the 1990s, more than 150,000 children from First Nations, Inuit, and Métis communities in Canada were forced to attend these institutions, known as residential schools. In the U.S., hundreds of thousands of children were forcibly placed in boarding schools between 1869 and the 1960s, according to the National Native American Boarding School Healing Coalition, which estimates that nearly 83 percent of school-aged Indigenous children attended the institutions in 1926.

The findings of Tuesday’s report follow a series of listening sessions held across the U.S. over the past two years, where former students have shared the harsh and often degrading treatment they experienced while separated from their families. A previous report from 2022 estimated that over 500 children died at the schools supported by federal legislation and policies. The institutions received more than $23 billion in inflation-adjusted federal funding.

The report recommends that the U.S. government carry out an official acknowledgment and apology for its role in implementing national policies for Indian boarding schools. Additionally, it calls on Washington to invest in solutions to address the ongoing impacts of the system, establish a national memorial, and identify and repatriate the remains of children who died at the schools.

Donovan Archambault, 85, from the Fort Belknap Indian Reservation in Montana, recounted being sent away to boarding schools at the age of 11, where he suffered abuse, was forced to cut his hair, and was prevented from speaking his native language. “An apology is necessary. They should apologize,” Archambault said. “But there is also a need for broader education about what happened to us. For me, it’s part of a forgotten history.”