OTTAWA -- Ottawa mayor Jim Watson says flags at City Hall will be lowered to half-mast starting Monday in memory of the 215 children whose remains were discovered on the site of a former Kamloops, B.C. residential school.

The children, some as young as three years old, were found buried on the site of the former residential school last week. The gruesome discovery confirmed what many survivors of the residential school system said they already knew, and sent waves of reaction across the country.

Plans are being made to identify the remains with the goal of returning them to their families and communities.

In a tweet Sunday morning, Watson said the flags at Ottawa City Hall would be lowered from May 31 to June 8.

"The flags will remain lowered for one hour for every child whose life was taken," Watson said.

Toronto mayor John Tory said his city would also be lowering flags for 215 hours this week, and other GTHA mayors followed

This comes after Mississaugas of the Credit First Nation Chief R. Stacey Laforme issued an open letter to Prime Minister Justin Trudeau, urging his government to lower flags across Canada and declare a national day of mourning. 

Trudeau tweeted Sunday afternoon that flags on all federal buildings, including the Peace Tower, would be lowered.

The Catholic Church ran the Kamloops residential school from 1890 to 1969. The federal government ran the site as a day school from 1969 to its closure in 1978. The National Truth and Reconciliation Commission had records of 51 deaths at the school between 1915 and 1963. has a list of resources and hotlines dedicated to helping Indigenous people in crisis here, as well as other provincial and national help lines here.

--With files from The Canadian Press.