National MP Mark Mitchell decries 'complete and utter failure' of Government's crime package after fatal dairy stabbing

National MP Mark Mitchell has decried what he says is the Government's "complete and utter failure" to crack down on escalating crime after the fatal stabbing of an Auckland dairy worker.

The worker was stabbed to death during an aggravated robbery in the suburb of Sandringham on Wednesday night.  

It's believed the offender left the store with the cash register and put it in a wheelie bin before the worker approached him and a fight broke out.

The alleged killer remains on the run.

"To the family who today mourns their lost loved one - I am so sorry this has happened. I know our Sandringham community is a tight-knit one and they will be feeling this deeply too," said Prime Minister Jacinda Ardern, who's also the MP for Mt Albert - the electorate where the dairy was located.

"Our job as Government is to make sure those who commit such crimes are brought to justice and to try and prevent them [from] occurring at all. On both counts, we will keep doing all we can," she said in a statement posted on social media.

But Mitchell, the National Party's Police spokesperson, said the Government's $6 million package aimed at supporting retailers targeted by crime, announced in May, had been a "complete and utter failure". 

His comments come after revelations the Sandringham dairy where the murder happened had applied for the crime prevention fund to buy fog cannons three times but was denied access.

Police Minister Chris Hipkins was trying to figure out why the dairy had not successfully accessed the Government funding for fog cannons, senior Labour MP Michael Wood told AM on Friday.

Mitchell, speaking to Newshub Late on Thursday, said frontline police officers also remained under pressure after Labour missed its 2017 goal of 1800 extra cops

Police numbers have increased under Labour, however - and it's on track to reach a net gain of 1800 police officers by June.

But Mitchell isn't impressed by that figure.

"It's the middle of next year now before they hit that target, so the police haven't got the numbers," Mitchell told host Isobel Ewing. 

"The police are under enormous pressure - our brave, thin blue line is stretched to breaking point and it's making their job extremely difficult, and it's very hard on the public when they want the police to be able to respond when they call for help."

Ewing asked Mitchell whether a community-based approach was the best way to crack down on the escalating crime.

Mitchell said social investment was "a cornerstone of our belief". He highlighted National's controversial "Combatting Youth Offending Plan" - which outlines proposals to send young offenders to military camps - released last week. 

While the Sandringham suspect did not appear to be a youth, Mitchell said New Zealand needed to "invest in people early and work with them until we get the outcomes".

Hipkins, who has been Police Minister since earlier this year when he replaced Poto Williams, on Thursday defended actions taken by the Government - saying there'd been significant progress with fog cannons, security alarms, bollards and roller doors. 

"Of course, I would have liked to have seen some of that happen sooner but I'm confident that work is now, as indicated, accelerating." 

Justice Minister Kiri Allan said the Government has expressed sorrow over the senseless attack and is focussing on supporting the victim's family, community and the police.