LONDON (AP) — London police said Friday that four men have been arrested on suspicion of aiding Iran by spying on the Jewish community.

In a statement, the Metropolitan Police said the suspects — one Iranian and three dual British-Iranian nationals — were taken into custody on suspicion of assisting a foreign intelligence service. The men, who were arrested at addresses in and around north London shortly after 1 a.m, are suspected on spying on locations and individuals.

Police said the men arrested are aged 22, 40, 52 and 55 and that searches are ongoing at the addresses as well as other properties nearby.

Six other men were also arrested on suspicion of assisting an offender and have been taken into custody, the force said.

“We understand the public may be concerned, in particular the Jewish community, and as always, I would ask them to remain vigilant and if they see or hear anything that concerns them, then to contact us,” said Commander Helen Flanagan, who is in charge of counterterrorism policing in London.

The arrests come as the U.S. and Israel continue to strike Iran, which has kept up retaliatory strikes on Israel, U.S. bases and across the region. Britain is not involved in offensive operations but is assisting in regional defense.

The Campaign Against Antisemitism said it is grateful to police “for foiling this alleged plot” but accused the British government of not taking the threat from Iran seriously.

“The U.K. may not be acting against Iran but Iran is acting against us,” it said in a statement.

“The government’s failure to keep its promise to proscribe the Islamic Revolutionary Guard Corps — the main instrument that the Islamic Republic uses to foment antisemitic violence worldwide — has sent the message that support for the brutal Iranian regime and its Jew-hating and West-hating ideology is perfectly acceptable in Britain,” it added.

Iran-related spying in the U.K. is an increasing concern for British authorities.

The head of Britain’s MI5 domestic intelligence service, Ken McCallum, said in October that more than 20 “potentially lethal Iran-backed plots” had been disrupted in the previous 12 months.

He alleged that Iran, along with Russia, is increasingly using “ugly methods,” including “surveillance, sabotage, arson or physical violence.” The U.K. has accused Iran of using criminal proxies to conduct attacks on European soil.

Most of the disrupted Iran-backed plots have targeted opposition Farsi-language media outlets or the Jewish community.