Canadians should prepare themselves for the discovery of sites similar to that of the former residential school in Kamloops, B.C., where the remains of an estimated 215 children have been detected, former senator Murray Sinclair said in a statement Tuesday.

Sinclair, who chaired the Truth and Reconciliation Commission (TRC), said the commission asked the federal government to allow it to conduct a fuller inquiry after hearing stories from residential school survivors that "proved to be horrendous."

"We submitted a proposal, as it was not within the mandate of the TRC, and that request was denied," he said in a statement. "So largely we did what we could, but it was not anywhere near what we needed to investigate. Now we are seeing evidence of the large number of children who died.

"We know there are lots of sites similar to Kamloops that are going to come to light in the future. We need to begin to prepare ourselves for that."

The TRC released 94 calls to action six years ago following a lengthy investigation into residential schools. It made six recommendations regarding missing children and burial grounds.

The commission called on the federal government to work with churches, Indigenous communities and former residential school students "to establish and maintain an online registry of residential school cemeteries, including, where possible, plot maps showing the location of deceased residential school children."

Sinclair said he's been inundated with calls from residential school survivors since last week's discovery. "Hundreds of calls, often just to cry. I can hear not only the pain and the anguish, but also the anger that no one believed the stories they had told," he said.

"I can also hear their sense that they have lost some hope that maybe those children that hadn't returned might still be found. They now know that may not happen."

Sinclair said it's critical to continue investigating to get a fuller picture of what happened at residential schools across the country.

"We need to ensure that we put in place healing programs and foundations that will help survivors to gather and share their memories and stories," he said.

I wanted to take the opportunity to speak to you regarding the situation that has come to the public's eye about the discovery of bodies at the residential school in Kamloops, British Columbia, Canada.

When I was asked to chair the Truth & Reconciliation Commission, I thought that I had a pretty good idea of what to expect. Discovering what was going on in the schools, I thought, would be accomplished by listening to what the survivors told us and recording their stories. I undertook that part of the work openly and willingly, with what I thought was a good understanding of what they were going to tell us.

But the stories from the survivors proved to be horrendous. One of the most common stories that we heard were from survivors who talked about the children who died in the schools and whose deaths they witnessed. Just as often, we heard about the loneliness and separation from their family — how they lost so much.

One aspect of residential schools that really proved to be quite shocking to me personally, was the stories that we began to gather of the children who died in the schools. Of the children who died, sometimes deliberately, it was at the hands of others who were there, and in such large numbers.

Survivors talked about children who suddenly went missing. Some talked about children who went missing into mass burial sites. Some survivors talked about infants who were born to young girls at the residential schools, infants who had been fathered by priests, were taken away from them and deliberately killed — sometimes thrown into furnaces, we were told.

We had no expectation that this would be a part of the work we were doing. We asked the government to allow us to conduct a fuller inquiry to that part of the work of the TRC, to explore that on behalf of the survivors and Canadian public. We submitted a proposal, as it was not within the mandate of the TRC, and that request was denied. So largely we did what we could, but it was not anywhere near what we needed to investigate. Now we are seeing evidence of the large number of children who died.

We know there are lots of sites similar to Kamloops that are going to come to light in the future. We need to begin to prepare ourselves for that.

Those that are survivors and intergenerational survivors need to understand that this information is important for all of Canada to understand the magnitude of the truth of this experience.

Since the revelation of what has happened at Kamloops has come to light, I have been inundated with calls from Survivors. Hundreds of calls, often just to cry. I can hear not only the pain and the anguish, but also the anger that no one believed the stories they had told. I can also hear their sense that they have lost some hope that maybe those children that hadn't returned might still be found. They now know that may not happen.

My heart goes out to the Survivors, the children and families of Survivors who never made it back. I know this is a hard time. But we must persevere in our investigation that we must know what happened at these schools. We need to ensure that we put in place healing programs and foundations that will help survivors to gather and share their memories and stories.

I pray for you all and hope that you can find a way to continue on in a good and healthy way.

Miigwech