The Knesset’s only immigrant from the English-speaking world, Rabbi Dov Lipman, has labelled a speech by a rabbi at a top Israeli yeshivah as a “tragedy”.

Last week, Nissan Kaplan, a rabbi at the prestigious Mir Yeshivah, whose classes draw upwards of 200 students, said in a discourse on the weekly Torah portion that he not only backed the killing of government ministers but that he educated his children in this spirit.

He told students that his five-year-old son said: “Daddy, we don’t have a sword in the house, I’m looking... maybe a hammer is also good? I was very happy, I gave him a kiss... I was so proud of my son, he’s looking for a sword to kill all these government ministers.”

His logic was that, because the government plans to draft the strictly-Orthodox into the army, its ministers are the modern equivalent of Haman, who tried to kill the Jews in the Purim story. They are also representatives of Amalek, the ancient foe of the Jews whose elimination is prescribed by the Bible. He claimed, too, to be invoking proclamations of Aharon Leib Shteinman, one of today’s most respected Charedi rabbis.

Commenting on the fact that the remarks were made in an English-language class mostly attended by non-Israelis, Rabbi Lipman said: “Overseas students should come to Israel to strengthen their Torah studies and their links to Israel and not to be imbued with hatred towards other Jews.”

In an interview with the JC, Rabbi Kaplan apologised for his statements, saying he “never meant such a thing”.

Aharon Leib Shteinman has strongly denied that there is any truth in Rabbi Kaplan’s claim that he branded government ministers as deserving of death. The supposed declaration “never happened”, said Rabbi Shteinman’s spokesman, Benny Rabinowitz.

But some self-appointed watchdogs of the Charedi community have suggested that there may be an attempt to cover up comments that were made.

“I read what Rabbi Kaplan told the media, I don’t think it was convincing,” said Shahar Ilan, vice president of research at Hiddush, an NGO that fights what it considers religious extremism. “I can’t see why he would invent such a thing if he doesn’t think it’s true. It’s much more logical that Rabbi Steinmann told it as a theoretical halachah and didn’t want to be quoted outside.”

On the apology, Mr Ilan said it was “important that Rabbi Steinmann’s spokesperson denied it and understands how serious sentences like this are”.

Neither the police, nor the Prime Minister’s Office or the Justice Ministry gave any comment on Rabbi Kaplan.

One senior British Jewish educator who is familiar with the yeshivah said, “I found his comment abhorrent, but from what I understand he is actually a very good guy and this was totally out of character… Mir Yeshivah is a very balanced environment and certainly not a centre for extremism.” A fundraising dinner for Mir in the UK attracted more than 1,000 supporters in 2012.