SACRIFICE and sadness will hang heavy in the air on Thursday for officers and wider family of the Mid North Coast Local Area Command.
It will be the 20th anniversary of senior constables Pete Addison and Bob Spears' murders at Crescent Head.
The two officers, stationed at Kempsey but both of whom lived in Port Macquarie, were killed while responding to a violent disturbance on Main Street about 1am on July 9, 1995.
Electrician John McGowan killed Sen Const Spears first by using a .223 calibre Rutger Rifle, before taking the other officer's life.
McGowan then shot himself.
The two officers were posthumously awarded the NSW Police Force's highest honour, the Commissioner's Valour Award, the following month.
More than 200 officers and guests are expected at Crescent Head's Killuke St memorial tomorrow at 10.30am to commemorate the fallen colleagues.
"It will be an opportunity for all colleagues to show we haven't forgotten what happened," Superintendent Paul Fehon said on Monday.
"It's for us to remember, and for us to let the families know we will never forget their bravery.
"There was an impact on so many people."
Police chaplain Father Paul Gooley will lead the service, which will be concelebrated by Fr John Casey who was the LAC's chaplain 20 years ago and conducted Sen. Const. Addison's funeral.
Police Commissioner Andrew Scipione will then present the National Police Service medals to the widows of the two officers to mark the men's heroism and diligence to duty.
Deputy commissioners Catherine Burn and Nick Kaldas will also be at the service, as well as former commissioners, politicians and the heads of Ambulance NSW and Fire and Rescue NSW.
Former State Coroner Derrick Hand, who investigated the murders, is another notable guest.
The general public is also invited to attend, with plenty of space available in surrounding parkland.
The slain officers' families will lay wreaths, followed by Commissioner Scipione and fellow police.
The community are also able to lay a wreath. A reception will take place following the ceremony at the Crescent Head Country Club.