Counties Manukau Detective Inspector Gary Lendrum said last week that the arrests came after members of the community came forward with invaluable information following a renewed focus on the unsolved murder.
Bush was shot dead 30 years ago at the tavern just before midnight.
He had been enjoying a drink with three other staff members after closing up the pub when two men burst in.
The two heavily disguised men, one carrying a double-barrelled shotgun and the other a baseball bat, stormed into the bar yelling, "this is a hold-up".
As Bush stood up, he was shot and killed. One of the men then ordered a female staff member to search Bush's pockets for the key to the safe.
The robbers fled with $25,000.
Lendrum said Bush's family had been through every family's worst nightmare and praised them for their courage, strength and bravery.
"We hope these arrests can offer them some degree of comfort and closure," he said.
