The Tk鈥檈mlups te Secwepemc announced in May last year that the remains of as many as 215 children were found using ground-penetrating radar around the former Kamloops Indian Residential School in British Columbia鈥檚 Interior. Since then, many other First Nations have also searched school sites in their territories.

Here is a timeline surrounding the events:

2021

May 22-23: A specialist using ground-penetrating radar makes preliminary findings that the remains of 215 children were buried around the site of the former Kamloops Indian Residential School.

May 27: Tk鈥檈mlups te Secwepemc Chief Rosanne Casimir issues a statement saying she has confirmed 鈥渁n unthinkable loss that was spoken about but never documented by the Kamloops Indian Residential School.鈥

May 30: Prime Minister Justin Trudeau announces that all Canadian flags in federal buildings are to be lowered to half-mast to honour the 215 and all other Indigenous children who didn鈥檛 make it home from residential schools.

June 11: Victoria city councillors vote unanimously to cancel Canada Day celebrations to allow for 鈥渢houghtful reflections鈥 about what it means to be Canadian after the discoveries in Kamloops.

June 23: The Cowessess First Nation in Saskatchewan says as many as 751 unmarked graves have been discovered near the former Marieval Indian Residential School.

June 30: The Lower Kootenay Band in B.C. says a search using ground-penetrating radar has found 182 sets of human remains in unmarked graves outside St. Eugene鈥檚 Mission School, a former residential school operated by the Catholic Church.

June 30: Survivors of a former residential school in the community of Lower Post in northern B.C. gather to mark the demolition of the facility.

July 13: The Penelakut Tribe announces in an online newsletter that more than 160 unmarked and undocumented graves have been found at the former Kuper Island Industrial School site near Chemainus, B.C.

July 15: Prof. Sarah Beaulieu of the University of the Fraser Valley says the discovery of a child鈥檚 rib bone and a tooth had triggered the use of ground-penetrating radar to search the apple orchard at the former Kamloops residential school site in May.

July 20: The B.C. government says it will provide immediate funding to 21 First Nation communities to help search for human remains at former residential schools or hospitals.

July 22: Vancouver police say there has been a 鈥渄ramatic increase鈥 in vandalism or mischief incidents against properties owned by churches, coinciding with reports of remains being found near Indigenous residential schools.

Sept. 30: Canada marks its first National Day for Truth and Reconciliation. Trudeau spent part of the day flying to Tofino, B.C., to join his family.

Oct. 5: The Federal Court approves the settlement of a class-action lawsuit for those who attended residential schools.

Oct. 7: The Tk鈥檈mlups te Secwepemc First Nation says Trudeau "missed an opportunity" to show his commitment to the survivors of residential schools by not replying to its invitations to take part in an event marking the first National Day for Truth and Reconciliation.

Oct. 18: Trudeau is rebuked by Casimir during his visit to the nation. Trudeau apologizes to those gathered, saying he regrets his decision not to spend the National Day for Truth and Reconciliation with them.

Nov. 7: The Canadian flag is returned to full mast ahead of Remembrance Day.

Nov. 9: Six Nations of the Grand River in Ontario begins a search for unmarked grave sites on the grounds of the former Mohawk Institute.

Dec. 7: A trip to the Vatican by Indigenous leaders and residential school survivors to meet Pope Francis is cancelled because of a new wave of COVID-19.

2022

Jan. 20: Canada's Crown-Indigenous Relations Minister Marc Miller announces an agreement with the National Centre for Truth and Reconciliation to hand over more records on residential schools that Ottawa had been holding back.

March 23: Indigenous organizations in Manitoba, officials from the City of Winnipeg and the provincial and federal governments form a council to support searches for burial sites of children who attended residential schools.

March 30: Trudeau visits Williams Lake First Nation in B.C.鈥檚 Cariboo region, saying 鈥渁ll of Canada grieves'' with the community after 93 鈥渞eflections'' were found in January that could indicate the burial sites of children around the former St. Joseph's Mission Residential School.

April 1: Pope Francis issues an apology for the role of the Roman Catholic Church in the harm caused to generations of Indigenous people by residential schools. 鈥淚 want to say to you with all my heart: I am very sorry,鈥 he says.

May 16: Miller says the searches on the grounds of former residential schools to date are just the beginning, with 140 former residential school sites in Canada.

This report by The Canadian Press was first published May 18, 2022.