Organisers say 15,000 people attended Sydney rally amid warnings of an unfolding humanitarian catastrophe in Gaza.

About 15,000 attended the rally in Sydney on Saturday, organiser the Palestine Action Group said, with protesters chanting “free, free Palestine” and “down, down Israel”.

Thousands more Australians attended rallies in Perth, Brisbane and Hobart, with more pro-Palestinian events scheduled to take place on Sunday in Melbourne and Adelaide.

“It’s difficult, what has been broadcasted in the Western media is definitely not reflecting what is on the ground,” Abdullah Ali, who attended the Sydney rally, was quoted as saying by the Australian Broadcasting Corporation.

“What I see is different … I see parts of children being put in plastic bags, it’s extremely hard for anyone to see.”

At least 4,137 people have been killed in Gaza since Israel began its bombardment of the enclave in response to attacks by Hamas on October 7, according to Palestinian officials.

Israeli Prime Minister Benjamin Netanyahu has pledged to continue the offensive on Gaza until the Palestinian armed group is eliminated amid expectations that Israeli troops will soon launch a ground invasion of the enclave.

Oxfam and United Nations agencies have warned that the enclave is facing a humanitarian catastrophe as residents risk contracting cholera and other deadly infectious diseases due to the collapse of water and sanitation services.

Saturday’s rally went ahead peacefully after receiving last-minute approval from police, following controversy over a previous event that featured anti-Jewish slogans.

Organisers had warned that anti-Jewish chants, flag burning and flares would not be tolerated during the event.

There were no reports of arrests.

New South Wales Premier Chris Minns had earlier promised “zero tolerance” for violence or hate speech.