The chief rabbi has said Jews in the UK are facing a “sustained campaign of violence and intimidation” after another attempted arson attack on a synagogue in London.

The incident at Kenton united synagogue in Harrow, north-west London, on Saturday night caused minor smoke damage to an internal room but no injuries or significant structural damage, according to the Community Security Trust, which monitors antisemitism and provides protection for Jewish communities in the UK.

The building is close to a school and children’s playground.

Police were seen searching a black SUV nearby on Sunday morning. A large cordon was in place and a forensics officer, fire investigation dogs and several plainclothes officers were working at the scene. One marked and about five unmarked police cars were outside the synagogue.

A senior counter-terrorism officer said the Met was looking into whether the series of arson attacks against Jewish sites were carried out by Iranian proxies.

Ephraim Mirvis, the chief rabbi of the United Hebrew Congregations of the Commonwealth, said in a statement on X: “Last night yet another synagogue, this time in Kenton, was targeted in a cowardly arson attack.

“It follows the attack in Finchley on Wednesday and the attempted attack on what was the Jewish Futures building in Hendon on Friday night, making three Jewish sites attacked in London in less than a week.

“A sustained campaign of violence and intimidation against the Jewish community of the UK is gathering momentum. This sustained attack on our community’s ability to worship and live in safety is an attack on the values that bind us all together.

“Thank God, no lives have been lost, but we cannot – and must not – wait for that to change before we understand just how dangerous this moment is for all of our society.”

According to police, a man had been spotted approaching a row of shops in Hendon carrying a plastic bag later found to contain three bottles of fluid. He placed the bag by a building, before lighting the items inside and fleeing the scene when they failed to fully ignite. The former Jewish Futures building sustained minor damage to its shopfront, with no injuries reported.

In a statement posted on X, Keir Starmer said: “I am appalled by recent attempted antisemitic arson attacks in north London.

“This is abhorrent and it will not be tolerated. Attacks on our Jewish community are attacks on Britain.

“We are increasing visible policing and those responsible will be found and brought to justice. We will not rest in the pursuit of perpetrators.”

The president of the Kenton united synagogue has called on Starmer to declare “an epidemic of anti-Jewish hate” in the wake of a series of arson and attempted arson attacks on north-west London sites.

Saul Taylor of the charity behind the Kenton united synagogue said: “The government and local police forces have responded well to the recent appalling attacks including Heaton Park Hebrew Congregation and Hatzola ambulances, but it is clear that more must be done to prevent these attacks occurring at all.

“The prime minister should declare publicly what the Jewish community has known for some time: this is an epidemic of anti-Jewish hate.”

Police forensic officers at the scene of an attempted arson attack at the former Jewish Futures building in Hendon on Friday. Photograph: Alishia Abodunde/Getty Images

The Metropolitan police had already deployed extra resources to parts of north-west London as it treated a separate attempted arson on Friday night as an antisemitic hate crime.

Counter Terrorism Policing London were leading the investigation into the incident in Hendon, in the borough of Barnet, as well as those into other attacks, due to the “similar circumstances and online claims of responsibility”, the Met said.

Speaking outside Kenton united synagogue, deputy assistant commissioner Vicki Evans, the senior national co-ordinator for counter terrorism, said: “The nature of the incidents has been similar – arson attacks targeting Israeli- and Jewish-linked premises in London.

“Most have been claimed online by the group Ashab al-Yamin (Islamic Movement of the Companions of the Right).

“This same group has claimed several incidents over recent months at places of worship, business and financial institutions across Europe. These locations all appear to be linked to Jewish or Israeli interests.”

She added: “I’ve spoken previously about the Iranian regime’s use of criminal proxies, and we’re considering whether this tactic is being used here in London.

“This is recruiting violence as a service, and the people who conduct that violence often have little or no allegiance to the cause and are taking quick cash for their crimes.”

On Wednesday, bottles, one thought to contain petrol, were placed near Finchley Reform Synagogue in Barnet, north London. Officers said two people wearing dark clothing and balaclavas were seen approaching the synagogue just after midnight. Neither of the bottles were ignited and the people fled the scene, the force added, with no damage or injuries reported.

And four Jewish community ambulances were set on fire in Golders Green in the early hours of 23 March.

A spokesperson for the charity Campaign Against Antisemitism said: “A synagogue in London was firebombed last night in what is now terrifyingly becoming a spate of daily arson attacks on the Jewish community.

“It betrays a cataclysmic failure of the state – politicians, police chiefs and prosecutors – to tackle antisemitic extremism in this country, which has gone largely unchecked for two-and-a-half years. Britain is fundamentally a different country now.

“Still the government refuses to proscribe the Islamic Revolutionary Guard Corps, an obvious first step to address foreign radicalisation and interference. It is shocking that concern for the sensitivities of a violent Iranian regime is more important to the government than the welfare of Jewish people in this country.”