Police have serious concerns for children at the Parliament protest and are urging caregivers to take them home.

"The site is no longer a safe environment for families and children," police said in a statement.

About 30 children are currently at the protest at Parliament grounds and authorities were aware of a number of protestors planning to travel to Wellington over the weekend, police said.

They say they are working with Oranga Tamariki to ensure children are at the forefront of planning and response decisions.

"The focus for police is to contain the current perimeters of the protest and continue to maintain a safe community for our Wellington residents."

Any vehicles that arrived and parked illegally outside the protest perimeter could be subject to towing and impounding, police said.

Police say they will continue to exercise judgment about the application of tactics.

A group of protesters have crossed Cook Strait and arrived in Wellington to join the occupation at Parliament.

Around 18 people, including children, were seen disembarking from a boat on Queens Wharf this afternoon.

Their luggage included backpacks, rolled up yoga mats and a stroller.

Dan Suter was one of those who made the crossing onboard the vessel Seddon Park, and was taking the sighting of a dolphin on the way as a sign.

"In a way, it's a symbol of freedom. No one's telling them to get a jab."

Suter, from Christchurch, said he wanted to see the protest first-hand. He wasn't sure how long he would stay.

Cat McGowan, 24, was another of the passengers - traveling to the protest to promote freedom.

Born in Ireland but based in Christchurch, McGowan said she would be staying at the protest indefinitely.

"As long as I can handle it, mentally," she said.

Asked whether she was concerned about clashes between police and protesters, McGowan said she wasn't worried for herself but for others who couldn't protect themselves.

The vessel's skipper, Greg, has been a fisherman for three decades and claimed to know Cook Strait well. He said everyone was wearing lifejackets.

"The last thing I want to do is harm anyone."

Earlier this week, Greater Wellington's Harbourmaster Grant Nalder said boaties should be aware of the crossing's dangers and their obligations upon entering Wellington.

It was the second trip Greg had made from Picton to Wellington. Today's journey took about 7 hours.

The 18 passengers had come from all over the South Island to get transported to Wellington. Greg said some had driven all the way from Southland to make the voyage.

Greg said there wasn't a set cost for passengers, it was largely based on donations. One passenger had contributed oil, another had offered to cut hair, others had given koha.

Greg, originally from Nelson but more recently based in Greymouth, said he'd had contact with Nalder on his initial trip and he said all discussions had been pleasant.

Asked whether he would continue transporting people if police or Maritime NZ asked him to stop, Greg felt it wasn't their business.

"[It's] nothing to do with them, I'm just [giving] my friends a lift."

Taking the Herald onboard the boat, Greg said the trips were joyful. People normally passed the time by chatting.

As it was Greg's permanent residence, the vessel was equipped with a self-contained shower and toilet. Two of his children, aged 10 and 11, had also made the trip over.

Written on the fridge by his son was the message "Friendly freedom pirates".

The group's arrived on day 18 of the occupation - a day that's been relatively quiet on the police front.

However Police Assistant Commissioner Richard Chambers has made it clear they remain committed to returning 'freedom of movement' to Wellingtonians.

He said the protest was having an unreasonably negative impact on residents, workers and students. 

"This has been a difficult and disruptive time for many local residents and businesses." 

Chambers also reiterated that the protest area was not safe for families, and said it was still far from being operated lawfully. 

Children were caught up in moves over territory yesterday as police manoeuvred more concrete blocks into place. 

As riot police moved from Lambton Quay to a Bunny St blockade, several officers barged into camping areas and pulled some children out, along with adults caring for them. 

The children were then stuck between riot police and a second line of police, until they were let through and able to cross the road towards the railway station. 

About five young children were left screaming and crying after the incident. 

Some children were caught up in stand-offs involving police and protesters near Parliament yesterday. Photo / George Heard 

One was sobbing, asking for her mother, while another, lying on the footpath as pedestrians walked by, would wail when concerned onlookers tried to move her. 

Paramedics were on the scene and handed over blankets but attempts to help were largely rebuffed by those aiding the children, still angry about what had happened. 

Mid-afternoon, some protesters laid several plywood shields on the ground and practised how they would pick them up if riot police charged. 

Some shields had messages on them, including "Make love, not war" and "What about your kids?" 

Opposition to Covid-19 vaccine mandates is the most common political issue protesters share, but a wide range of people and viewpoints are present at the site. 

A Herald photographer met a man named Phil, who was arrested earlier this week and had a black eye. 

At the protest near Parliament, an attendee named Phil said he was arrested the other day. Photo / George Heard 

At about 4.30pm, riot police retreated and protesters maintained their line. 

A few minutes later, police moved back into an intersection, behind the concrete blocks. 

Protesters largely maintained their line on the other side of the blocks, inside the occupied zone. 

Police also formed a line on Bunny St with officers near concrete blocks at the intersection of Bunny and Featherston Sts. 

The forklift moved bollards to further block access to the road. The area was more complicated for police to navigate as it was still partially open to traffic. 

"The protest area is not safe for families, and it is still far from being operated lawfully," police Assistant Commissioner Richard Chambers said. 

"This has been a difficult and disruptive time for many local residents and businesses." 

Chambers said police were committed to returning freedom of movement to Wellington. 

He said the protest was having an unreasonably negative impact on residents, workers and students. 

Police have still not directly answered claims of "friendly fire" earlier this week made in a video doing the rounds on social media. 

The Herald has been asking police for more than a day for a clear response to the claims, in which some commentators say a police officer pepper-sprayed a colleague. 

A woman peers between riot shields during a police operation to move concrete blocks on Day 17 of the Covid-19 convoy protest and occupation at Parliament. Photo / Mark Mitchell 

A protest attendee on the steep steps in front of the Beehive said the people present were ordinary New Zealanders. 

The man said the mainstream media presented issues in a negative and untruthful way and there was nothing violent about the protest. 

He said issues including his opposition to vaccine mandates and concerns about Jacinda Ardern's "globalist" agenda brought him to the protest. 

He said this was his second visit to the occupation but before that he had never been to a protest in his life, and he felt it was wrong to fire people for not getting vaccinated. 

He said was not afraid of catching Covid-19. 

The protest site was yesterday deemed a Covid-19 location of interest after some attendees tested positive for the virus. 

Meanwhile, Act leader David Seymour said a chaplain who won't get a booster shot after a bad second dose reaction personified why Government vaccine mandates should not apply to schools. 

Act released its Covid-19 policy yesterday, saying MIQ should be ditched immediately but some face mask rules should stay. 

And it said Government vaccine mandates should be dropped but health providers, businesses, councils, and private property owners could make their own rules. 

Seymour said a school chaplain in Epsom had a terrible reaction to a second shot and didn't want to get a booster. 

"He's been mandated out of this job. He had to have the booster. I just think that's nuts." 

Seymour said under Act's policy, institutions would set their own rules. 

He expected retirement villages would take a hard line on vaccines but many other places would choose less restrictive rules. 

Workers, volunteers or unpaid workers at schools are subject to mandatory vaccination orders. 

Police in riot gear hold a crowd of protesters at bay during their operation to move barriers on Thursday. Photo / Mark Mitchell 

Health and disability workforces, if eligible for a booster, are required to have boosters by today. Some exemptions are available. 

"However, there are very few situations where vaccination is contraindicated and, as such, a medical exemption is expected to be rarely required," the Ministry of Health website stated. 

"Exemptions will be limited to situations where a suitable alternative to the Covid-19 vaccine is not readily available for the individual," it added. 

In these sectors, a booster dose is mandated six months from the end of one's primary vaccination course. 

Minister of Education Chris Hipkins is expected to make an announcement on masks and give an update on rapid antigen tests for schools this morning. 

Yesterday afternoon, a man who allegedly drove a car at police during the Wellington protests was granted bail. 

Name suppression lapsed for Joseph Witana, 53, who was charged with assaulting police using a car as a weapon earlier this week. 

The homeless man from Wainuiomata pleaded not guilty and elected a trial by jury. 

He was ordered to stay out of Wellington and not travel south of Ngauranga Gorge, except to attend court or see his barrister, Kevin Preston. 

The Bail Act prohibited reporting of some details about the hearing. 

Witana will next appear in court in late April. 

He appeared from custody by audiovisual link before Judge Andrew Nicholls at Wellington District Court. 

- By Adam Pearse and John Weekes, NZ Herald