Zoe Garbett, Sadiq Khan, Rob Blackie and Susan Hall were at the event.The two frontrunners in the race for City Hall clashed on policing, transport and housing at the only hustings event they are likely to attend.Conservative candidate Susan Hall accused Labour incumbent Sadiq Khan of a serious failure on crime.Mr Khan said putting a Tory in charge of police would be like "getting an arsonist to put out a fire".The event on Thursday was organised by Jewish organisations.Both Mr Khan and Ms Hall vowed to do more to tackle anti-Semitism and make Jewish people feel safer.But there were angry exchanges over who would build the most homes and best help Londoners get around the city.The candidates vying to be the next London mayor Mr Khan was interrupted with shouts of "no" from some in the audience when he blamed crime levels on austerity, which saw police budgets and youth provision cut after 2010.
"It has consequences," he said.
Ms Hall said: "It's amazing to hear Sadiq Khan try to defend his record.
"We have had eight years when violent crime has risen 33% and knife crime is up 54%."
Susana Mendonca/BBC Mayoral election candidates at a hustings eventSusana Mendonca/BBC
Sadiq Khan and Susan Hall clashed on policing, transport and housing
She said without offences rising in London last year, overall levels of knife crime would have fallen in England and Wales.
Mr Khan said: "The idea of a Tory candidate talking about more police is like asking an arsonist to put out a fire."
He accused his Tory opponent of "shirking" responsibility and failing to condemn government cuts, while Ms Hall vowed to "restore" borough-based policing, recruit 1,500 more officers and add two new police "bases" to every borough.
Asked for their views on the slogan "From the River to the Sea" chanted at pro-Palestinian marches, Mr Khan said it depended on the context.
"Park for a second freedom of speech and the law, if you know that causes distress and anxiety to your Jewish friends and neighbours don't chant it," he said.
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Ms Hall said a "red line" on behaviour at protests in central London had been passed some time ago, and there was "no context" in which the chant was anything other than antisemitic.
With the Green and Liberal Democrat candidates sharing a platform with him, Mr Khan did not take the opportunity to repeat his recent appeal to their supporters to back him to ensure he defeated Ms Hall.
Lib Dem candidate Rob Blackie said the Tories might be "in freefall" but Mr Khan did not deserve to win, while the Greens' Zoe Garbett said she was offering hope for people suffering amid the cost-of-living crisis.
"In London today there are people who are out to work before the sun rises and back after it sets, while not earning enough to pay their energy bills and put food on the table," she said.
Mr Khan was accused by his Tory opponent of stifling house-building with bureaucratic restrictions that left him behind on his targets.
Susana Mendonca/BBC Audience members at the hustingsSusana Mendonca/BBC
The event was organised by the London Jewish Forum
"You hear him speak about home starts," she said. "But a start is only a hole in the ground, it's not somewhere you live," she said.
As Labour mayor for eight years, Mr Khan claimed to have built more council homes than at any time since the 1970s, with the promise of thousands more if he had the backing of a Labour government.
Ms Garbett, who rents her flat in Hackney where she said she could not hope to buy, told those gathered that she would focus on getting rents down because "that gets to the heart of the city I want to live in," while Mr Blackie said he would loosen planning conditions to increase the number of homes built.
On transport, the Lib Dem candidate accused Mr Khan of denying London's transport system vital investment through "election gimmicks" like freezing fares. " If you take money out of the system, the system creaks."
Ms Garbett claimed she could find the money to provide free bus travel for people up to the age of 22 and could restore free peak-time travel to people over 60.