LONDON — A series of arson and vandalism attacks on Jewish sites in Britain were the work of a proxy group backed by Iran, the U.K. government said Monday.

The government said it is banning the Islamic Movement of the Companions of the Right, or IMCR, also known as Harakat Ashab al-Yamin al-Islamia.

It also banned Iran’s powerful paramilitary Revolutionary Guard as a threat to national security. Committing sabotage on behalf of the groups will be punishable by up to life imprisonment after Parliament approves the legislation, which the government expects to take place by the end of the week.

Security Minister Angela Eagle said in a statement that the IMCR has claimed seven attacks in the U.K. The group had said online that it was responsible for a string of arson attacks on Jewish sites in London in recent months, including fires at synagogues and Jewish charity ambulances, as well as a Persian-language media organization critical of Iran’s government. No one were injured in the blazes.

“Sitting behind IMCR were members of Iran’s Islamic Revolutionary Guard Corps Qods Force, who almost certainly directed IMCR attacks across Europe,” she said. Quds, or Jerusalem, Force is the Guard’s expeditionary unit.

The group sprang up online earlier this year and has also claimed responsibility for synagogue attacks in Belgium and the Netherlands.

Law enforcement officials and intelligence experts say Iran-backed proxy groups are behind a growing number of attacks in Europe, most targeting the Jewish community and Persian-language media critical of Iran’s Islamic government.

They typically work by recruiting members of criminal groups to carry out sabotage and other attacks.

Authorities said Monday that Britain is also designating the GRU Volunteer Corps, a group controlled by Russia’s military intelligence agency, as a national security threat. The U.K. says the group conducts foreign intelligence collection and hostile covert operations on behalf of the GRU.

Authorities said the new measures will make it easier for police and intelligence agencies to tackle what they call “thugs for hire,” or anyone supporting the proxy groups.

“We have already taken tough action against the Iranian regime and those linked to it, and against Russian operatives and networks targeting our country. These new powers will make it easier to prosecute and lock up anyone carrying out their dirty work here in Britain,” Prime Minister Keir Starmer said in a statement.

The bans come under a new U.K. law that took effect last week, giving the government powers to tackle proxy organizations carrying out hostile activity on behalf of foreign states.

Earlier this month, two Romanian men were given prison sentences over the stabbing of a journalist from a Persian-language television station, an attack the judge said was carried out on behalf of the Iranian state.

There was no immediate comment from Iran.

The European Union in January listed the Revolutionary Guard as a terrorist organization over Tehran’s bloody crackdown on protests.