Jeremy Corbyn's support for the two people jailed for their role in the 1994 London bombings of Israel’s embassy and a Jewish charity building has been criticised as “particularly disturbing” — not least because community buildings now require heavy protection as a consequence.

Mr Corbyn was part of a campaign to free Samar Alami and Jawad Botmeh, who were convicted of conspiracy to cause explosions after the car bomb attacks on July 26.

The first exploded at the embassy, injuring 14. Thirteen hours later, a second bomb exploded, injuring six, outside Balfour House in North Finchley, home to a number of Jewish charities, including the Joint Israel Appeal, forerunner of UJIA.

Simon Johnson, chief executive of the Jewish Leadership Council, said it was “vital that Mr Corbyn, especially in light of his previous acquaintances with unsavoury individuals and groups, takes robust action to eliminate antisemitism, extremism and terrorism, all of which, of course, are linked.

“His support for the two people who were convicted for their role in the 1994 bombings is particularly disturbing. Our community buildings are now heavily protected and secured, in part because of those events.”

Moshe Raviv — Israel’s ambassador to the UK from 1993-98 — told the JC: “The wall behind my desk, was destroyed. There was glass everywhere. It was sheer luck nobody was killed.”

A furious row is raging over whether Mr Corbyn laid a wreath at a 2014 ceremony in Tunis, honouring the terrorists behind the 1972 Munich massacre, and Mr Raviv claimed the Labour leader “had not changed his views and support for terrorism.

“In London he supported the convicted terrorists — a straight line can be seen from there to what happened in Tunisia.”

Asked if he had a message for Mr Corbyn, Mr Raviv replied: “There is not much I can say — it is he who has to explain why he supported the perpetrators of this heinous attack.”

In 2013, Mr Corbyn wrote a letter saying he had supported Botmeh “in Parliament and outside, including in meetings/demonstrations. Jawad’s case is, I believe, a miscarriage of justice.”

Additionally, the JC has found that as late as 2010, a “human rights” category on Mr Corbyn’s old website linked to an organisation named “Freedom and Justice for Samar and Jawad.” This claimed there had been an “MI5 cover up” and suggested that “Israeli intelligence could have been involved in the attacks”.

A Community Security Trust spokesman commented: “Jeremy Corbyn needs to urgently clarify exactly which parts of this conspiracy theory he does and does not believe.

“Let us also remember that the bombings caused extreme concern throughout the UK Jewish community. It would be good if Mr Corbyn could clarify what anti-racist support he gave us at that very difficult time.”

The JC has found no evidence of any support for British Jewry voiced by Mr Corbyn after the bombings.

Both Alami and Botmeh pleaded not guilty, maintaining they had nothing to do with the attacks. However, Alami admitted that, 13 days before the bombings, she had accepted two boxes which contained quantities of the explosive TATP. As reported by the JC at the time, she had also used a false name to rent a storage unit in Acton, West London, where police found two improvised bombs made from TATP, electrical timers, guns and ammunition.

When detectives searched an apartment said to be owned by a family member of Alami, they found, behind a trap door, a Cobra pistol with ammunition and documents including some from a book titled The Engineering of Explosives.

At the Old Bailey trial, Botmeh said he and Alami had experimented with explosives but claimed they were for use in territories occupied by Israel. Although admitting he was connected with the bomb-making equipment discovered in Acton, he said he had hidden it there in a “panic” after hearing about the London explosions.

The defendants were represented by Michael Mansfield, QC, who showed the jury a 30-minute film concerning the First Intifada, saying: “What happened there has ramifications here.”

He also submitted letters containing leniency pleas to the judge, one from Hanan Ashrawi, a senior Palestinian politician, who said injustice had led to people carrying out acts they would not have “in normal circumstances”.

The two were convicted in December 1996. An appeal was dismissed in 2001 and a second appeal rejected by the European Court of Human Rights in 2007. Botmeh was released in 2008; Alami in 2009.

Between 2001 and 2005, Mr Corbyn signed five Early Day Motions, co-sponsoring one, calling for the pair’s release.

The EDMs said “Samar Alami and Jawad Botmeh have always protested their innocence” and claimed the convictions had been “widely questioned”.

A spokesperson for Mr Corbyn said this week: “Jeremy believed that there had been a miscarriage of justice. He, of course, condemns all terrorist acts.”