Police have fired rubber bullets at protesters massing at the Cenotaph, after earlier turning fire hoses on the mob. 

Police in riot gear have shunted protesters off Parliament's lawn, only for fresh skirmishes to flare up at the corner of Lambton Quay and Bowen St. 

Meanwhile, protesters have thrown a rock and smashed the glass doors to Victoria University's Pipitea Campus and set fire to a rubbish skip outside in Bunny St. 

Prime Minister Jacinda Ardern says she is "both angry and deeply saddened" to see Parliament's grounds "desecrated" by protesters as police forced the occupation off the precinct. 

While she said police expected hostility, resistance and violence "it is another thing entirely to witness it". 

Three police injured in the violence have been taken to hospital. 

Asked how she hoped the occupation would be resolved, Ardern said: "I hope they will put down their weapons and police will arrest them." 

Ardern's comments came after police said protesters deliberately torched tents and a playground slide during violent skirmishes with officers. 

Several tents at the site were set on fire this afternoon, with firefighters rushing to the scene to put out the blaze. A slide at Parliament's playground was also torched. 

Police on the move during their early-morning operation on day 23 of the protest at Parliament, Wellington. Photo / Mark Mitchell. 

As officers cleared Parliament's lawns police said protesters deliberately set several tents on fire. 

"These actions put both protesters and emergency service staff at significant risk." 

Protest spokesman Leighton Baker was among those pepper-sprayed and arrested, his family says. 

Police appear to have now regained control of the Parliament grounds, with the space cleared out as officers moved quickly to clear tents, gazebos and other items from the space that has housed the protesters for 23 days. 

Ardern said earlier today that the protesters had been given "ample opportunity" to leave the site as police kicked off a "major operation" to clear the area that started in the early hours of the morning. 

"The protest has been at times been violent and fuelled by misinformation and conspiracy theories." 

It had also turned into a Covid-19 superspreader event. 

Ardern earlier today acknowledges the work police had done, saying today had been difficult. 

Police commissioner Andrew Coster said earlier officers were undertaking a "major operation" today to clear the roads and restore order to the impacted areas of the capital. 

"The operation is the result of significant planning and the commitment of several hundred staff from around the country." 

Today's police action followed an escalation in concerning behaviour, and the protest had reached a stage where the harm being done far outweighed any legitimate protest. 

"This has never been about preventing lawful protest." 

A protester is treated after being pepper-sprayed during the early-morning police operation on day 23 of the protest at Parliament. Photo / Mark Mitchell 

By midday today, 36 people had been arrested on a range of offences – including wilful trespassing, obstruction, wilful damage, assaults police, possession of a weapon, and refusing to provide identifying details. 

Police had towed 15 vehicles, including a number of vans, campervans and trucks. The vehicles had been seized and would not be returned in the immediate future, Coster said. 

When Ardern earlier today was asked if she had agreed with the approach up to that point, she said that had been for Coster to decide. 

However, she said she believed there should be a review of whether more could have been done earlier to prevent things from reaching the stage they had. 

She said the aftermath would include checking whether Parliament's own security was sufficient – but she would be concerned about anything that felt as if it was distancing Parliament from the public.