Just under a month after it was reported that the remains of over 200 children were discovered at a residential school in British Columbia, Indigenous leaders are saying that an even larger amount were found at another school.

According to a report USA Today published earlier today (June 24), Indigenous leaders say that 751 unmarked graves were found at Marieval Indian Residential School, an institution that operated in Saskatchewan between 1899 and 1997. Bobby Cameron, who works as Chief of the Federation of Sovereign Indigenous First Nations in Saskatchewan, has spoken out about the discovery.

“This was a crime against humanity, an assault on First Nations,” Chief Cameron said before saying he thinks that more bodies will continue to be discovered. “We will not stop until we find all the bodies.”

While the graves are currently unmarked, that reportedly wasn’t always the case. According to Cowessess First Nation Chief Cadmus Delorme, the Roman Catholic Church removed the markers. The Catholic Church has been criticized for their role in facilitating these residential schools, which tried to convert Indigenous people to Catholicism while forcing them to attend these schools and abandon friends, family, and their own way of life as they faced various forms of mental and physical abuse. Members of Indigenous tribes still want records from all of the residential schools so that they can document everything that happened.

A couple of weeks ago, Kinistin Chief Felix Thomas suggested that Catholics boycott mass until Pope Francis apologizes for the church’s role in the residential schools. Now, Chief Cadmusn Delmore is also saying the Pope should offer up an apology.

“The Pope needs to apologize for what happened,” he said. “An apology is one stage in the way of a healing journey.”

You can see Indigenous leaders speak on their findings about the 751 unmarked graves below. Stay tuned for more updates as further details become available.