LONDON — The U.K.’s chief rabbi said Sunday that British Jews are facing “a sustained campaign of violence and intimidation” after attempted arson at a London synagogue, the latest in a string of similar attacks.

The incident that caused minor damage to Kenton United Synagogue on Saturday night follows a series of blazes at Jewish-linked premises and an Iranian opposition outlet that are being investigated by counterterror police.

Chief Rabbi Ephraim Mirvis said on X that “a sustained campaign of violence and intimidation against the Jewish community of the UK is gathering momentum.

“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,” he added.

Prime Minister Keir Starmer said he was “appalled” by the attacks, and pledged that “those responsible will be found and brought to justice.”

London’s Metropolitan Police force said it has sent extra uniformed and plainclothes officers to northwest London after attacks in the past month on synagogues, Jewish charity ambulances and a Persian-language media organization critical of Iran’s government.

The Kenton synagogue arson came a day after an attempt to ignite bottles of fluid outside the former offices of a Jewish charity on Friday night.

No one has been injured in any of the incidents. Several people, ranging in age from teens to people in their 40s, have been arrested and charged.

Police said they have not formally linked the incidents, but Counter Terrorism Policing London is leading the investigations because of “similar circumstances and online claims of responsibility.”

Online posts have claimed responsibility in the name of Harakat Ashab al-Yamin al-Islamia. Israel’s government has described the group, whose name means the Islamic Movement of the Companions of the Right, as a recently founded group with suspected links to “an Iranian proxy” that has also claimed responsibility for synagogue attacks in Belgium and the Netherlands.

The group also posted a video claiming Israel’s London embassy was going to be attacked with drones carrying dangerous substances. Police said the embassy was not attacked, but the force shut the nearby Kensington Gardens park on Friday as officers examined discarded items including two jars containing powder. Police said nothing harmful was found.

The U.K. has accused Iran of using criminal proxies to conduct attacks on European soil targeting opposition media outlets and the Jewish community. Britain’s MI5 domestic intelligence service says that more than 20 “potentially lethal” Iran-backed plots were disrupted in the year to October.

Some security experts say Harakat Ashab al-Yamin al-Islamia is likely a flag of convenience rather than a coherent group, and its claims should be treated with caution.