© N/A Rachel Riley edited a well-known image of Jeremy Corbyn Pic: Twitter/@RachelRileyRR Countdown star Rachel Riley is facing calls to be sacked after she edited a photo of Jeremy Corbyn at an anti-apartheid protest and accused the Labour leader of being "racist".

The TV star prompted an online row after she posted a photo of herself wearing a t-shirt adorned with an image of Mr Corbyn.

In the image on Riley's clothing, the Labour leader is seen being escorted by two police officers with a placard hung from his neck that reads: "Jeremy Corbyn Is A Racist Endeavour."

The image has been edited from an original photograph, which pictured Mr Corbyn being arrested at an anti-apartheid protest in London in 1984 during his first year as an MP.

In the unedited photograph, Mr Corbyn's placard reads: "Defend The Right To Demonstrate Against Apartheid Join This Picket."

Riley posted the photo of her wearing the t-shirt on Twitter on Tuesday evening, when Mr Corbyn took part in a TV debate with Prime Minister Boris Johnson.

The debate was broadcast from the same studios where Countdown is filmed.

© Getty Rachel Riley Riley, who is Jewish, has been a frequent critic of Labour and Mr Corbyn over allegations of antisemitism and accused him of failing to properly address the issue.

She wrote on Twitter: "I didn't feel comfortable knowing my workplace was to be full of racists tonight.

"I don't endorse Boris, but I do endorse #NeverCorbyn."

Riley has since been criticised for altering the image of Mr Corbyn, with the hashtag "#sackRachelRiley" trending on Twitter on Thursday evening.

Andrew Feinstein, a former member of South Africa's parliament for ex-president Nelson Mandela's African National Congress party, described Riley's action as "deeply repugnant".

Mr Feinstein, who now lives in the UK and is supportive of Mr Corbyn, tweeted: "As a former MP under Nelson Mandela, as the son of a Holocaust survivor who lost 39 members of her family in the camps, as a Sth African anti-racist, I find what Rachel Riley has done offensive, appalling & deeply repugnant."

However, Riley defended herself and posted a series of links to articles which reported the ANC once advised Mr Mandela against meeting with the anti-apartheid group Mr Corbyn was a member of in the 1980s, as it was not part of the mainstream Anti-Apartheid Movement.

© Getty Rachel Riley

The articles also includes claims Mr Mandela was advised the group had hindered the campaign to abolish South Africa's racist laws.

Riley tweeted: "The ease at which large swathes of people can be mobilised into group hate, for highlighting Corbyn's history of racism using an image of his arrest as part of an extreme group cited as damaging the mainstream anti-apartheid movement, is just one reason Jewish people are worried.

"Trying to brand me as racist for this, whilst lauding themselves as anti-racist heroes, shows just how little regard many people have for anti-Jewish racism, and why I and many others speak so loudly. It's a hatred which unites the far right, far left and is having a resurgence.

"I won't dignify this with any further response & I won't tolerate abuse from those who choose to rank one form of racism over another, that's hypocrisy. They're all unacceptable."

A spokesman for Mr Corbyn did not comment.

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