Police have arrested and charged more than 20 people after a pro-Palestinian protest at Sydney’s Port Botany blocked a road leading to the shipping facility on Tuesday night.

In chaotic scenes, police from the riot squad and officers on horseback tried to break up the protest, which included children. Officers dragged protesters from the road after they failed to comply with an order to move on. At one point, protesters lifted a child in a pram over the top of the crowd.

The protest, which began at 6pm, was directed at Israeli shipping company ZIM, which has offered its support to the Israeli government in its fight with Hamas in Gaza and had a ship at the port on Tuesday.

About 400 people gathered near a boat ramp at Foreshore Road at Botany, waving flags and calling for a ceasefire in Gaza. They were met by officers from Operation Shelter and other units, including the public order and riot squad and police on horseback.

Police said protesters moved towards the intersection of Sirius and Foreshore roads and occupied Foreshore Road, blocking vehicle movement. Officers issued move-on directions to a number of people in the group, but they did not comply and 23 were arrested. Foreshore Road was cleared about 9pm.

Organiser Ahmed Abadla, from Palestine Justice Movement Sydney, said the police had been violent towards the protesters, who he said had blocked Sirius Road, a smaller access road to Port Botany, not Foreshore Road.

“There was dragging, pushing, shoving. There were elderly women and girls, and kids in the protest, and they didn’t respect that,” Abadla said.

“We aim not to have any violence incorporated into our rallies. Police started the whole thing and the crowd got angry.”

He said the mood at the protest changed suddenly when protesters tried to pack up food they had brought to give to Port Botany workers, and the child in the pram, whom he believed was aged about four, had been seated near the food, at the side of the protest.

“We feared that something would happen and we started moving very quickly, but the police were not helpful in waiting for us,” Abadla said.

“We wanted to move the pram from harm’s way. [The police] saw it, they saw the child in the pram, but unfortunately, they didn’t pay any regards to that.

“We were peacefully protesting the violence that was happening in Gaza, that was point of the whole of the rally really – to send a strong message to ZIM, to boycott ZIM, and to send a message to government.”

Those arrested were taken to several police stations, where they were charged with failing to comply with a move-on direction and damaging or disrupting a major facility.

When asked if the protesters were still in custody, a police spokeswoman said details of court appearances would be provided later on Wednesday.

NSW Premier Chris Minns condemned the protests and said the police had his unqualified support. He said he had been briefed on the incident and dismissed the suggestion police had acted inappropriately.

“Look, I completely reject it,” he said. “There was a lawful police order given to the protesters to move on, and it was only after ample time was given to the protesters to leave the roadway and allow commerce to transact in that port were arrests effected.

“We cannot have a situation where our ports are blocked for commerce because one group or another has a political disagreement with another country. That would be hugely damaging to our economy.”

Minns said police had helped facilitate 73 largely peaceful protests in the past six weeks and the government would defend the right for people to protest lawfully.

Police Minister Yasmin Catley also said the police “did a great job” when she appeared on ABC TV.

Federal Home Affairs Minister Clare O’Neil told Channel Nine’s Today that the protest activity “was utterly despicable” and she hated to see violence against the police.

“We’ve got a bunch of people in our country who are feeling incredibly deeply about what’s going on in the Middle East … let’s respect each other, understand the strong views and feelings in the community, but just calm down a bit,” O’Neil said.

Executive Council of Australian Jewry co-chief executive Alex Ryvchin said the protest showed the pro-Palestinian movement was about hatred and destruction, not peace.

“These actions are a threat to public safety, and they incite violence and hatred. There is a co-ordinated effort to marginalise and endanger Jewish Australians and rip our society apart and it must be stopped.”

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