A million-dollar reward has been announced for information about the murder of security guard Gary Allibon in a 2010 armed robbery.

NSW Police and Allibon’s widow Monica Allibon will today announce the reward would be increased ten times over from the previous amount of $100,000 to $1 million to encourage community members with information on his death to come forward.

Allibon and another guard were entering a commercial building on Sydney’s Sussex Street to replenish an ATM on June 7, 2010, when they were stopped by a group of armed men. Allibon was shot before the offenders stole the cash and fled in a stolen Audi S8 sedan.

The 59-year-old was taken to Royal Prince Alfred Hospital by paramedics but later died.

In a previous appeal, Monica Allibon said she hoped the reward could convince someone to “provide detectives with the missing links they need to catch Gary’s killer”.

“My husband was killed by someone who can only be described as a cold-blooded murderer,” she said.

“The murder of someone you love changes your life forever.”