A Reform UK election candidate compared transgender and non-binary people to Adolf Hitler and called gay pride a “sin” in online posts that have been criticised as “sick and unacceptable”.

David Carpin, who will stand for the right-wing populist party in the Henley and Thame constituency at the General Election, defended the controversial Facebook posts he made last year as “freedom of expression”.

One of them placed pictures of transgender swimmer Lia Thomas, transgender TikToker Dylan Mulvaney, and non-binary singer Sam Smith alongside the Nazi leader and asked who people would save from a burning room.

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Other posts called trans women “mentally ill men” and LGBT pride a “sin” and replaced the stars in the European Union flag with swastikas.

This is Oxfordshire: One post seemed to compare transsexual and non-binary people to Adolf HitlerOne post seemed to compare transsexual and non-binary people to Adolf Hitler (Image: Contributed)

Conservative parliamentary candidate for the Henley and Thame seat, Caroline Newton, criticised the posts.

“Freedom, including freedom of speech, is something millions died for last century,” she told the Oxford Mail.

“Invoking Adolf Hitler and Nazi symbols in defence of it is staggeringly insensitive and contemptible.”

This is Oxfordshire: Another post was a cartoon which called trans women mentally ill menAnother post was a cartoon which called trans women mentally ill men (Image: Contributed)

Labour's candidate for Banbury, Sean Woodcock, added: "To invoke Hitler in a live and legitimate debate about trans people and their rights, is not only idiotic but similarly unacceptable and offensive.

This is Oxfordshire: Mr Carpin's caption on this post said gay pride was a sinMr Carpin's caption on this post said gay pride was a sin (Image: Contributed)

"Whatever your views on Brexit, to compare the European Union to a regime that is responsible for a world war that led to tens of millions of deaths including the cold-blooded murder of six million Jews in death camps, is sick and utterly unacceptable. 

"It's insulting to the memory of the victims of that barbaric regime. 

"It is also an insult to those service personnel, some of whom are still alive and living in the Henley and Thame constituency, who fought against that regime.

"Mr Carpin is clearly not fit to be an MP."

This is Oxfordshire: He also posted the EU flag with stars replaced by swastikasHe also posted the EU flag with stars replaced by swastikas (Image: Contributed)

Responding to the criticism, Mr Carpin, who lives in Woodcote and works in IT, said: “The posts provide the opportunity for discussion and criticism, since the UK constitution upholds freedom of expression.

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“All are within the law of the land and none are directed at named individuals.”

This is Oxfordshire: The General Election is expected to happen this yearThe General Election is expected to happen this year (Image: NQ)

Mr Carpin has tried to be elected to South Oxfordshire District Council twice - for Reform UK last year and for UKIP in 2019 - but was unsuccessful both times.

His current party, Reform UK, which grew out of the Brexit Party, has previously pledged to ban gender lessons in schools.

Come the election, which is expected this year, the populist fringe party could be a thorn in the side of Prime Minister Rishi Sunak by taking right-wing votes from the Tories.

This is Oxfordshire: Caroline Newton, Conservative candidate for the Henley and Thame seatCaroline Newton, Conservative candidate for the Henley and Thame seat (Image: Caroline Newton)

In Henley and Thame, Mrs Newton, who was announced as the Tory candidate on Saturday (February 17), faces a fierce battle to succeed John Howell and retain a typically safe seat held by the Tories since 1910.

A YouGov national survey last month predicted the Liberal Democrats, whose candidate is Freddie van Mierlo, would win the seat.

Labour has not announced a candidate yet while the Green Party has chosen Jo Robb.