09/28/2014 01:17 EDT | Updated 11/28/2014 05:59 EST

National memorial pays tribute to five peace officers killed while on duty

OTTAWA - A booming two-gun salute thundered over Parliament Hill on Sunday as three Mounties killed in a shooting rampage in New Brunswick were remembered, along with a Toronto police constable and a Saskatchewan conservation officer who also died in the line of duty last year.

Hundreds of police and peace officers from across Canada and as far away the U.K., along with pipe and drum bands, marched onto the hill to honour the five slain officers.

"There's nothing we can say and there's nothing we can do that will ease the pain of your loss," said an emotional Dennis Brock, president of the Canadian Peace Officers' Memorial Association, as he spoke to the family and friends of those killed.

"All of us in the law enforcement family share your sorrow."

Constables Douglas Larche, Dave Ross and Fabrice Gevaudan were killed and two other RCMP officers were injured on June 4 in Moncton.

Toronto police Const. John Zivicic died last November after his cruiser was involved in a collision. Saskatchewan conservation officer Justin Knackstedt was killed after being hit by an SUV while he was directing traffic at the scene of a crash in May 2013 near Saskatoon.

With their families seated on the Parliament Hill lawn, the five were honoured in a memorial held annually for those killed while keeping the country and Canadians safe.

The remembrance is held on the last Sunday of every September and was established in 1998 by the federal government to give Canadians the opportunity to express their appreciation for the work of police and peace officers.

Public Safety Minister Steven Blaney told the memorial the officers represented all of those who protect Canada's citizens and communities from people who threaten them.

"As police and peace officers do in Canada every day, these fallen officers stood for us against elements that threaten the safety and security of our communities," said Blaney.

"They stood for us against those who would do harm to our country, our communities and our families."

Justin Bourque, 24, has pleaded guilty of three counts of first-degree murder and two counts of attempted murder in connection with the Moncton shootings. He has yet to be sentenced.

The first Canadian police officers memorial in 1978 honoured 14 officers. There are now more than 840 names of fallen officers on the list, which has been expanded over the years to include all officers killed in the line of duty.

The names of the five honoured Sunday will be added to a granite stone that stretches along the base of a police memorial pavilion which was erected behind Parliament's Centre Block in 1994.

Follow @tpedwell on Twitter