"When they left they have taken the victims' vehicle," Clayton said.
The white Toyota station wagon was found a short time later with the front window smashed out in Stace Hopper Dr, Marsden Cove.
The victims were able to free themselves and call 111.
"This appears to be a well planned robbery," Clayton said.
"The victims were very traumatised."
Police said it was unclear how the thieves had arrived at the tavern - on foot or having been dropped there by someone else.
Officers were reviewing security camera footage today as part of the investigation.
Clayton asked for anyone who saw any suspicious activity around the tavern before 11pm on Wednesday or saw the vehicle being dropped at Marsden Cove between 11.30 and midnight to contact police.
If you can help police contact Detective Geoff Bigwood at Whangarei station on 09 430 4500 or if you want to remain anonymous call Crimestoppers on 0800 555 111.