New Alert Level 4: This COVID-19 lockdown is different with new rules to combat Delta and police mean business

To combat Delta which is COVID-19 supercharged, the Government is supercharging lockdown, adding more restrictions starting with mandatory mask wearing from Thursday.

If you break the rules, you break the law - and police have already started cracking down.

The lockdown came into effect at midnight on Monday, and for some Dunedin students Newshub caught up with, it meant preparing - but not commiting - until the precise strike of 11.59pm. 

"We're isolating in 30 minutes," a group of male students told Newshub. A group of girls added, "Until 12am, we will be out on the street."

And as sure as day follows night, lockdown follows Delta. The eerie Armageddon-esque empty streets of alert level 4 are back, replacing the bustle of last night's busy bars. 

And the supermarket scramble began for some classic Kiwi necessities. 

"Get me a few beers and a few essentials," one man told Newshub. 

It's been more than a year since our last alert level 4. COVID-19 was scary then and now that we're dealing with Delta, it's terrifying - terrifying but beatable.

"Level 4 restrictions are there to protect everyone and make this lockdown as short as possible," Prime Minister Jacinda Ardern said on Wednesday. 

To keep it as short as possible, level 4 is being supercharged. From Thursday, everyone over 12 years old must wear a mask when visiting or working in essential services - places like supermarkets, pharmacies, petrol stations and cabs.

Also, when at public transport terminals - railway stations and bus stops - masks are mandatory.

"Please take responsibility for yourself and show care of others. Wearing a mask is an act of service to the people around you," Ardern said.

And if you don't show that care you'll have to answer to the mask police - literally. 

"A fine for not wearing a mask, and then if there's a direction to wear a mask and there's no reason why they're allowed to decline and they fail to follow that direction, then an arrest is theoretically possible," said Police Commissioner Andrew Coster. 

If you need further convincing that police mean business, just look at failed politician and conspiracy theorist Billy Te Kahika. He was one of four people arrested during an anti-lockdown protest in Auckland on Wednesday. 

Here's the truth - a basic fact - breaking lockdown rules puts lives at risk and Delta is deadly.

"If we're looking at the tip of the iceberg, with what we now know as the Delta variant, then roughly speaking, we might be looking at 100 cases out there at the moment," said Auckland University disease modeller Professor Shaun Hendy.

Police are taking it deadly seriously. 

"We've seen how desperate the situation has become in other places," said Coster. 

So once again, desperate times call for desperate measures.

"What I just ask everyone to do is help us," said Ardern. "We will get on top of this if everyone plays their part."