A woman accused of attacking an Auckland supermarket worker this week has been charged with common assault.
The police were called to Countdown in Warkworth on Thursday.
In a video posted on social media, National's Mark Mitchell said the supermarket's manager was assaulted by a person waiting to enter the store.
"There was a flashpoint. A confrontation developed out of that and as a result, the...manager was assaulted and punched in the face."
Mr Mitchell said he was briefed by Warkworth police and urged people to be more tolerant.
"We have to be supportive of one another and encourage one another, we are all in this together."
A 45-year-old woman has been arrested and is expected to appear in the North Short District Court next month.
Countdown's general manager of corporate affairs, safety and sustainability Kiri Hannifin described the attack as demoralising and distressing.
Staff are sacrificing a lot to ensure the supermarkets stay open, she said.
"The level of abuse our team is facing is completely unacceptable and the fact we're also getting physically hurt is beyond words."
Customers waiting in lines outside stores are verbally abusing staff, as well as threatening to cough and spit on them, she said.
Staff at the Warkworth store are shaken and upet, but looking after one another, she said.
"They are shaken and obviously very upset, but it's like a family in that store and they're all looking after each other and they keep getting up and going back to work, it's incredibly humbling."
There were a number of abusive incidents across supermarkets this week as the country went into lockdown.
A checkout staff member told Checkpoint on Tuesday there have been daily tears, racial abuse and - in some cases - violence.
"I've had a few bad experiences since Covid-19 came to New Zealand," the checkout supervisor told Checkpoint.
She said she was looking after her own children and her father. Her partner is also an essential worker.
"We've had people throwing things at us, spitting at us, swearing at us, putting us down, calling us names, being racist to us as well.
"I had a male come in… he threw a basket at me because there was nothing on the shelf.
"He said to me 'why the f*** haven't you got stock on the shelf, you should have the stock on the shelf.'
On Monday, a woman who was denied entry to a Dunedin supermarket responded by coughing on staff and abusing them.