The anonymous tip line Crime Stoppers has been around for nearly 40 years and involves more than 100 programs across Canada. However, last week's tip about a planned mass-shooting in Halifax has been called ‘the most-significant ever received in this country.’

It was an anonymous tip that stopped a potentially deadly crime in its tracks, a plot to kill as many people as possible at the Halifax Shopping Centre on Valentine’s Day.

Retired police officer Ron Cheverie came into the Crime Stoppers office early last Thursday morning and was working through his alerts when he found an alarming tip.

“The hair came up on the back of my neck,” says Cheverie.

Cheverie quickly forwarded the tip to police and homeland security.

“Got on the phone to make sure they got the information because of how serious it was, they took it from there. Next thing I heard, some people were in custody,” says Cheverie.

And on the day the shooting was to happen, Cheverie went to the scene where the murderous plot was supposed to unfold.

“Well my wife and I happened to go to the Halifax Shopping Centre. We were walking around, I said to her, ‘look at these families walking around here,’” says Cheverie. “You know, you say my God, how tragic this could have been. You know, trying to talk about it sometimes you get choked up because you know what could have happened, an awful lot of lives would have been lost, so proud to be a Crime Stopper.”

The major break is shining new focus on the crime fighting program.

“It’s a Crime Stoppers tip like no other,” says John O’Reily, president of Nova Scotia Crime Stoppers. “It’s a great time to be a volunteer with crime stoppers.”

Crime Stoppers was founded four decades ago by a Maritimer in Albuquerque, New Mexico.

“Greg MacAleese, a Canadian born police officer from New Brunswick started the program,” says O’Reilly.

Stumped in a murder investigation, MacAleese went to his police chief to pitch an idea, make a plea for anonymous tips and offer of a reward. Just hours after a re-enactment of the crime aired on TV, he got his tip and solved his crime.

Today, there are more than 1,700 programs in 23 countries worldwide, still running on the same premise that started years ago.

With files from CTV Atlantic's Marie Adsett