(AFP) A day after his party was accused of painting a presidential campaign rival in an anti-Semitic light, conservative candidate François Fillon finally called for those responsible to be punished.

Fillon’s Les Républicains party was accused of attacking the independent centrist Emmanuel Macron on anti-Semitic grounds on Friday, the same day a leftist rival drew an awkward parallel between Macron’s campaign and Nazi gas chambers.

The two incidents are a watershed of poor taste in a remarkably tumultuous campaign. The lead-up to April 23’s first presidential election round has already been punctuated by the constant drumbeat of scandals affecting key players, namely Fillon and far-right leader Marine Le Pen.

On Friday, the conservative Les Républicains party tweeted a caricature that appeared to borrow heavily from anti-Semitic 1930s iconography depicting Macron encircled by allies. The former French economy minister was drawn with a long hooked nose and a top hat, using a sickle to cut a conspicuous cigar.

The caricature sparked a considerable outcry on social media, which led to its replacement with a photograph of Macron looking glum. On its Twitter account, Les Républicains said it wanted to “avoid any pointless controversies”.

“The use of terms and images that tap into the anti-Semitic imagination is extremely preoccupying with regard to the republican quality of debate but also with regard to the state of mind that prevails among the management of some [campaigns],” En Marche! spokesman Benjamin Griveaux told Agence France-Presse on Friday.

Alain Jakubowicz, president of the International League Against Racism and Anti-Semitism (LICRA) had expressed his consternation Friday on France Info radio. “It’s absolutely terrifying. I don’t know if I want to scream, cry or give up,” he said.

Fillon, for his part, tweeted a statement condemning the drawing more than 24 hours after the incident, saying he would not “tolerate” his party’s dissemination of caricatures that use markers of “anti-Semitic propaganda” and calling the cartoon “unacceptable”.

“I understand the emotion it may have triggered because it alluded to drawings from a sombre period in our history and conveyed an ideology I have always fought against,” Fillon said. “Political combat is tough but it must remain dignified,” he added, saying he had asked the party’s secretary general to punish those who have given the party an “image totally contrary to our values”.

Bernard Accoyer, Les Républicains’ secretary-general, had apologised in an initial statement published Friday evening “to those who may have been hurt or offended”, referring to the caricature that “may have been misinterpreted”. Accoyer added, “I want to issue a reminder of the total commitment our movement has to defending the values of the republic.”

On the same day, a political figure on the left was tripped up himself by off-colour comments.

Vincent Peillon, who finished fourth in the left-wing primary that saw Benoît Hamon win the Socialist Party nomination in January and now serves on his former rival’s presidential campaign team, was asked to elaborate on earlier comments pointing to Macron as “the experimental verification of [Marine] Le Pen’s remarks” about the “UMPS”, the derisive mash-up acronym the far-right leader has used for years to pointedly conflate the conservative Les Républicains party, formerly known as the UMP, and the Socialist Party (PS). “It seems to me there are folks from the UMP and the PS that are getting together,” Peillon explained.

The former education minister then appeared to hazard an odd, muddled parallel between eclectic support for Macron’s campaign and one of the darkest moments in European history. “You know, there is, happily, something stubborn about history – that is how we knew there were the gas chambers and that we cannot deny it. Today there are people from the UMP, [former Jacques Chirac cabinet minister Jean-Paul] Delevoye, I believe, and there are folks from the PS, [former Socialist Paris mayor Bertrand] Delanoë, I believe…” before being interrupted by the journalists interviewing him. Asked to clarify his reference to gas chambers, Peillon said, “For a simple reason: I am speaking about facts. You tell me I must be interpreting. My thinking is that facts are obstinate…”

The reaction from Macron’s party to Peillon’s remarks was again swift, calling the “comparison between En Marche! and Nazi gas chambers” a “point of no return” and calling for Hamon to dismiss Peillon from his campaign team. The En Marche! spokesman also said in a statement posted on Facebook, “So things are clear: to reach their goals, [Macron’s rivals] consider that anything goes, including now borrowing the worst tricks of the Le Pen family. The remarks this morning are as good as those held by the leadership of the National Front.”

Peillon conceded to a “clumsiness” in his remarks, but said his withdrawal from the campaign was “out of the question”.

“I refuse this controversy. It is dishonest and irresponsible to have people believe I was making a comparison between this political movement, En Marche!, and a tragic episode of history,” Peillon told AFP. “I wanted to remind people that we have the right to say facts and that we must be careful to not let people manipulate them, just as one must not manipulate public opinion in having people think I would lump things together in a way that I didn’t,” the Socialist added.