Anti-extremism organisation Mainstream UK has urged Sir Keir Starmer to take action against dozens of elected local councillors who expressed questionable - and in some cases antisemitic - views under previous leader Jeremy Corbyn.

According to Mainstream UK, set up by former Labour MP Ian Austin, many of those councillors have received little or no sanction for their conduct – although Labour rejects this claim.

An investigation by the anti-extremism group has highlighted examples of councillors using language that allegedly breaches the International Holocaust Remembrance Alliance definition of antisemitism, likening Israel to the Nazis and pushing hard-left conspiracy theories that accuse the Jewish state of being behind the 9/11 terror attacks.

The accused councillors include Labour group and deputy group leaders, ex-mayors and cabinet members.

Mainstream UK points out that some were suspended only to be readmitted to the party with a slap on the wrist. However, it is understood that of nine councillors highlighted to Labour by the JC in recent days, five are in fact still under investigation.

In High Peak Borough, Labour councillor Rachel Abbotts, elected in the Ward of Howard Town in May 2019, was reported to the party in February 2019 for sharing a post in 2016 on Facebook that said the “Jews declared war on Germany in 1933”.

The post added: “Jewish leaders, in combination with powerful international Jewish financial interests” boycotted Germany “for the express purpose” of damaging the economy to bring down the Nazis.

Cllr Abbotts had posted this content in reply to her partner, Mark Abbotts, who had written on Facebook that “people seem to forget that it was the Jews who declared war on Germany”.

She later said that she was “deeply and sincerely sorry” for the post and had not intended to condone an “obviously wrong and clearly antisemitic claim” and she “absolutely did not agree with the claim and told my partner so verbally.” She added they both had “serious health issues” at the time and her partner had subsequently realised he “was wrong”.

She received no sanction because the national party said it had received no complaint and the local party said she had shared the post without commenting on it and it had found “no evidence of antisemitism” from Cllr Abbotts.

In the London Borough of Hounslow, Nisar Malik was re-elected to the council in May 2018, despite being under investigation by the party after he shared a video that claimed “Zionist Jews” were behind the 9/11 attacks.

Cllr Malik also shared a post which claimed terror group Isis had been created by Israel and America. The post also called for a probe into the influence of the “Israeli lobby” in UK politics and cast doubt on the Syrian regime’s responsibility for chemical attacks.

At the time Hounslow’s Labour MP Ruth Cadbury branded the posts “completely unacceptable”. He received a reminder of conduct from Labour.

In the East London Tower Hamlets Borough Mohammed Pappu was elected in May 2018 to serve the Blackwall & Cubitt Town ward.

In October of that year it was revealed that, in December 2015, Cllr Pappu had shared a post accusing the UK of attacking Syria to “install a Rothschild bank”.

Following the revelation, Tower Hamlets Labour leader John Biggs called for Cllr Pappu to be expelled. He said: “I am very clear that these views are incompatible with being a Labour Party member”.

Mr Pappu subsequently delivered a lengthy apology, in which he outlined that he had referred himself to the party’s Standards Committee and was “willing to undergo training”.

He said: “I know that my actions let down my party and the borough and I am truly sorry…there is no place in our council, in our politics or in our society for the views represented in the material which I forwarded.”

A November 2018 report by the East London Advertiser said that, following the apology, an investigation was “not required” by Labour.

Cheryl Raynor was elected to Lancashire’s Wyre Council in May 2019. One month earlier she reportedly said “the media are lying about antisemitism in the Labour Party”. It was also noted that she had retweeted an article called: “The British-Israel partnership driving antisemitism allegations”.

Cllr Raynor was given a reminder of conduct notice.

George McIrvine is a Labour Party councillor who was elected in 2017 onto Dundee City Council.

Cllr McIrvine was reported to the Scottish Labour leader in April 2018 for sharing a Facebook post which said: “There are only nine countries left in the world without a central Rothschild bank: Russia, China, Iceland, Cuba, Syria, Iran, Venezuela, North Korea and Hungary. Isn’t it funny we are always at war with these countries.”

According to The Courier, Cllr McIrvine claimed he “intended the post to be viewed as a comment on banks in general rather than those owned by the Jewish Rothschild family”.

He received an official warning. The recent leaked Labour report into antisemitism appears to reveal that Scottish Labour leader Richard Leonard had called for the councillor to be suspended over the issue.

However, a former UK party official stated in an email: “The allegations have been considered and it does not amount to antisemitism so there will not be further action.”

The Mainstream UK report listed further examples of councillors who had posted inflammatory comments relating to Israel and Jews, including the well-publicised example of Jim Sheridan, the former Labour MP for Renfrewshire West who was elected onto Renfrewshire Council in May 2017.

Mr Sheridan was suspended in August 2018 after posting on Facebook that: “For all my adult life I have had the utmost respect and empathy for the Jewish community and their historic suffering. No longer due to what they and their Blairite plotters are doing to my party and the long-suffering people of Britain.”

Cllr Sheridan was reinstated to Renfrewshire Council’s Labour group in January 2019. In a statement, he wrote: “Whilst I am delighted with this decision, I remain of the view that my accusers were misguided and overreacted to what was intended to highlight my personal frustration and criticism of those intent on undermining our leadership… I would also like to reiterate my sincere apologies to the Jewish community whose historic struggle I have supported all my political life.”

A Labour spokesperson said: “We take all complaints of antisemitism extremely seriously, and they are always fully investigated in line with our rules and procedures and any appropriate action taken. We have strengthened and sped up how we deal with cases in recent years and we’re committed to doing more to root out this evil from our party and our movement.”