Organisers of a pro-Palestine rally want an apology and widespread retractions after police deemed “gas the Jews” might never have been chorused on the steps of the Sydney Opera House.

Footage of people chanting in the forecourt of Australia’s most famous building – including a caption highlighting the slur – drew global outrage and caused a domestic firestorm following the October 7 attacks by Hamas in Israel.

But police on Friday took a different view, based on a forensic analysis of numerous audio and video files of the demonstration by an “eminent” biometrics expert.

They “concluded with overwhelming certainty that the words used were, ‘Where’s the Jews?'” Deputy Commissioner Mal Lanyon said on Friday

Mr Lanyon accepted offensive terms including “f*** the Jews” were chanted while noting difficulty in attributing the words to specific people who could be charged.

The snap rally on October 9 was sparked by a decision to light the Opera House’s sails in the colours of the Israeli flag after the Hamas attack that sparked the latest Israel-Gaza conflict.

Several protesters held signs criticising Israel and its government, including descriptions of the nation as a terrorist state.

Chanting erupted and flares were let off after the protest officially concluded.

Several witnesses signed statutory declarations that they heard the “gas” phrase but in light of the forensic analysis, Mr Lanyon said the captions on the footage represented an opinion.

“Accurate information” in the public arena was important, he said.

The Australian Federation of Islamic Councils called for prosecutions of those who disseminated “false claims” that had unfairly vilified Palestinians and Muslims and harmed the “delicate fabric” of social cohesion.

The Australian Jewish Association on Friday however stood by the captioned footage it shared with news organisations and on social media, while the peak body for the Australian Jewish community added: “The world knows what was said.”

“A mob of thugs gathered at one of our nation’s most cherished sites to celebrate the mass slaughter and rape of Israelis, to burn Israeli flags and to chant threateningly towards fellow Australians,” Executive Council of Australian Jewry co-chief executive Alex Ryvchin said.

Protest organiser Palestine Action Group, which long maintained the “gas” chant was never uttered, called for widespread media retractions.

Spokesman Josh Lees suggested the wrongly captioned video was designed to damage the movement, pointing to “a long history of false claims of anti-Semitism used to silence critics of the state of Israel”.

“Many (in the media) should have known that this video was dubious or an outright fake,” he told AAP.

He also called on Premier Chris Minns to apologise for using the behaviour on October 9 to “demonise” protesters and thwart future rallies.

At the time of the protest, the premier led a host of prominent figures condemning the rally and the “shocking and abusive” comments reportedly made there.

However, the police analysis did not budge the state leader’s views on the events outside the Opera House.

“The protest was violent and racist,” Mr Minns said in a statement.

“Hate speech and racist language have no place in NSW.

“If those comments were made about any other group my reaction would be the same.”

The “gas” chant was cited numerous times during debates over hate crime laws including when MPs in November streamlined the procedure for police to start prosecutions.

NSW Opposition Leader Mark Speakman also criticised police for approving the march and warning the Jewish community to steer clear of the Opera House forecourt.

The ugly scenes preceded dozens of peaceful pro-Palestine demonstrations across the nation, including several attended by thousands of people in Melbourne and Sydney.

All Sydney rallies have been co-organised with a Jewish organisation, highlighting the movement was not opposed to those of faith, the Palestine Action Group said.