Minneapolis, Minnesota - New documentation has revealed 115 additional Indigenous boarding schools than previously reported by the US government.

The National Native American Board School Healing Coalition has released a new interactive map of 523 known boarding schools in 38 states targeting Indigenous Peoples across territory now claimed by the United States, The Washington Post reported.

Previously, the US Department of the Interior (DOI) had reported 408 such "schools" operated or supported by the federal government, including 21 in Alaska and seven in Hawaii, between 1819 and 1969.

The new list, the result of a three-year project, identifies 115 additional "schools" in operation starting in 1801, many of which were run by religious groups and institutions. Nine of the "schools" were opened after 1969 – beyond the time frame considered in the DOI report.

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Boarding schools in what is now the United States and Canada saw Indigenous children systematically ripped away from their families and forced to abandon their languages and customs in a large-scale ethnocide. Many survivors of the institutions were subjected to horrific physical, emotional, and sexual abuse, while thousands are believed to have died.

"We’re getting to a place where [the survivors are] starting to pass away, and we want to make sure the truth is known and the truth is told, so there’s some measure of justice because we’re all impacted as Native people," National Congress of American Indians President Fawn Sharp told The Washington Post.

Questions surrounding why the locations were not reported by the government remain.