Dozens of protesters lay on a busy CBD intersection, fake bodies were put outside offices and a factory was disabled in a nationwide protest against the war in Gaza.
Pro-Palestine group A15 Action called on supporters to blockade "the arteries of capitalism" as part of Monday's action, saying "the global economy is complicit in genocide".
A15 Action said the protests were in retaliation for the federal government's actions since Israel declared war on Hamas in Gaza.
"We will make it economically unviable on a widespread scale for Australia to continue to support Israel in committing genocide in Gaza."
Victoria Police confirmed 14 people were arrested, including 12 near the Boeing factory in Port Melbourne where the road was blocked.
Melbourne Activist Legal Support responded and accused teams of up to eight officers of aggressively arresting individuals.
Another two protesters were arrested, accused of tampering with traffic lights in Carlton.
More than 100 people gathered at BP's Melbourne office to object to the oil giant's presence in the Middle East.
Amongst their tactics was the use of fake bloodied bodies outside the building, before heading towards Southern Cross Station where the group then lay at the corner of Spencer and Bourke Streets.
They then marched up Collins Street, beating drums and chanting.
The group said further protests were planned in Melbourne's northwest on Monday afternoon.
Victoria Police said it respected people's right to protest when it is lawful and peaceful.
"However, there is no place for anyone wanting to deliberately disrupt and cause harm in our community," a Victoria Police spokeswoman said.
The West Gate Freeway, Hoddle Street, Thales' premises and the main access point to Melbourne’s docks were morning protest points but failed to attract significant crowds.
In Brisbane, more than 50 protesters gathered outside the Ferra engineering facility.
Police manned the gate to the facility, preventing protesters from entering, but no arrests were made.
"It makes you distraught to see the kind of violence that is going on that we are funding with our tax dollars," one protester, Ollie, told AAP.
"It makes complete sense that we the people of Brisbane, and the people of Australia want to do something about it."
Ten of the protesters danced around a sign reading "Ferra arms genocide" with Palestinian flags.
Near Hobart, protesters shut down operations at a workshop of Currawong Engineering after entering its factory.
University student CT, who disabled the company's workshop, said Currawong was "aiding and abetting the Israeli military".
In NSW three protesters blocked Thales' Rydalmere site by attaching themselves to devices, including a ladder and a gate.
Protester Lilli Barto, who was at the western Sydney premises, said the group wanted the government to stop supporting weapon suppliers.
Victorian Greens leader Samantha Ratham joined more than 100 protesters outside state parliament.
“What we’re going to see today is what we’ve seen for months across the world with millions of people joining these marches,” she said.
“(This is what) happens when our governments don’t listen."
In NSW, Premier Chris Minns said many officers were dealing with the aftermath of the deadly Bondi Junction stabbing tragedy.
"People need to understand that you may lose more supporters for your cause than you gain as we direct police resources to the inquiry," he told ABC News Breakfast.
"And the community itself is (trying) to come together after a terrible 48 hours".
The fresh protest comes days after Foreign Minister Penny Wong said the “pathway out of the endless cycle of violence” in the Middle East can only come with recognition of “a Palestinian state alongside the state of Israel”.
On October 7, Hamas - designated a terrorist group by the Australian government - launched an attack on Israel that killed 1200 people and led another 200 to be taken hostage.
In the months since, Israel has launched a ground offensive and bombing campaign on Gaza that has killed more than 33,000 people and displaced another 1.7 million, according to the local health ministry.
