An echoing peal of cannon fire signalled the start of a moment of silence in St. John鈥檚, N.L., and throngs of people along the city鈥檚 two main downtown streets fell quiet and bowed their heads.

Canadians are gathering today to honour the sacrifice of men and women in uniform who gave their lives in service of the country鈥檚 values and principles.

Prime Minister Justin Trudeau and Gov. Gen. Mary Simon are expected to pay their respects in a ceremony at the National War Memorial in Ottawa.

They will be joined by this year鈥檚 Silver Cross Mother Maureen Anderson from New Brunswick whose two sons, Sgt. Ron Anderson and Sgt. Ryan Anderson, served in Afghanistan.

Anderson, whose sons both died after a battle with post-traumatic stress disorder, will represent the mothers left behind by all service members killed in the line of duty.

The mournful sound of the Last Post will also be heard at many other cenotaphs and monuments across the country, as Canadians take a moment at 11 a.m. to pay silent respects to the fallen.

鈥淭hroughout our history, the men and women of the Canadian Armed Forces have kept our country safe,鈥� Trudeau said in a social media post as preparations began in Ottawa.

鈥淪ome returned home from the battlefield and were never the same. Others never returned at all. It is a debt we can never repay, and one we will never forget.鈥�

鈥� With files from Sarah Smellie in St. John鈥檚, N.L.

Laura Osman and Jim Bronskill, The Canadian Press