Canada flew its flags at half-mast Sunday in mourning for 215 children whose remains were discovered on the grounds of a former boarding school. The incident set up more than a century ago to depressurize indigenous peoples.

Canadian Prime Minister Justin Trudeau said on Twitter that "To honor the 215 children whose lives were taken at the former Kamloops residential school and all Indigenous children who never made it home, the survivors, and their families, I even have asked that the Peace Tower flag (in Ottawa) and flags on all federal buildings be flown at half-mast." Several municipalities, including the economic metropolis of Toronto, announced they would also lower their flags.

The discovery of the children's remains sparked strong emotions throughout Canada, particularly within the indigenous communities.

In the late 19th century, the Kamloops Indian Residential School was the largest of 139 boarding schools. It set up with up to 500 students registered and attending at any one time. The school operated by the Catholic Church on behalf of the Canadian government from 1890 to 1969. Some 150,000 Indian, Inuit, and Metis youngsters in total were forcibly enrolled in these schools. Their students were physically and sexually abused by headmasters and teachers who stripped them of their culture and language.

Ceremonies to honor the young victims took place or were to take place throughout the country. About 100 people gathered Sunday in the Mohawk community of Kahnawake.

To tribute to the victims, participants placed children's shoes and toys on the steps of the Saint Francis Xavier church as a tribute to the victims.