The Conservatives have suspended their candidate for Aberdeen North over allegedly antisemitic, Islamophobic and homophobic tweets he wrote seven years ago.

Ryan Houghton apologised for the posts, which included questioning evidence of the Holocaust, and claimed they had been taken out of context.

The posts were first highlighted by the National. One said that although there was “no credible evidence to suggest the Holocaust did not happen … I do find some of the events fabricated”.

He was also quoted as saying he did not see how homosexuality was good for the human race, that Islam’s core teachings had the goal of “world domination” and that some Muslims had big families with the aim of creating “Eurabia”.

A spokesman for the Scottish Conservatives said: “The comments contained in these blogs are unacceptable and Mr Houghton has been suspended as a member of the Scottish Conservative party as a result. The party has also withdrawn its support for his candidacy in Aberdeen North. The Scottish Conservatives deplore all forms of Islamophobia, homophobia and antisemitism.”

Houghton said in a statement: “At the age of 20 on an online forum, I took part in a range of political discussions. These included terrorism, LGBT rights and antisemitism.”

He said that in one of the threads he had discussed freedom of speech and comments made by the Holocaust denier David Irving, referencing his view that some evidence had been fabricated. Houghton said he made clear in subsequent posts that he was not defending the views and strongly opposed Holocaust denial.

The candidate added: “I apologise unreservedly for any hurt now caused by these comments and have been in contact with members of the Jewish community in Aberdeen.”

Although the Conservatives have removed their support for Houghton, he will remain as their candidate on the ballot because his nomination papers have already been submitted.

The Labour peer Alf Dubs said: “As someone who survived the Holocaust, I feel sickened that there will be a Conservative party candidate on the ballot paper on 12 December who claimed events in the Holocaust were fabricated. The Conservatives must face up to their problem with antisemitism. Instead of using the issue to score political points, they should challenge it in their own ranks.”

Aberdeen North was won in 2017 by the SNP’s Kirsty Blackman, with Labour in second place.

Separately, the Conservative candidate in Ashfield, Lee Anderson, has been criticised for saying “nuisance tenants” should be forced to pick vegetables and live in a tent in a field.

In a Facebook video, he said: “What I am about to say is my own personal opinion. I stood on this spot a few months ago, banging on about nuisance tenants on this lovely estate. People say to me: ‘But they’ve got to live somewhere.’ That’s right, so my plan would be – and again, this is just my own personal opinion – that these people who have to live somewhere, let’s have them in a tent in the middle of a field.

“Six o’clock every morning, let’s have them up, let’s have them in the field, picking potatoes or any other seasonal vegetables, back in the tent, cold shower, lights out, six o’clock. Same again the next day. That would be my solution.”

Layla Moran, a spokeswoman for the Liberal Democrats, said: “Everyone in this country deserves a decent standard of living. Conservative candidate Lee Anderson’s comment exposes a concerning disregard for this basic human right, and a lack of empathy towards those whom he aspires to represent.

“As a Conservative parliamentary candidate in a marginal seat, Anderson should not be stoking and entrenching division, or targeting vulnerable people. Unfortunately, this sort of comment is all too common from Conservative party candidates, who are out of touch with the constituencies and the people they are attempting to represent.”