The campaign group Leave.EU has defended a now deleted tweet it sent out about Islam in London.
The post refers to the capital as "Londonistan" and features a photo of Mayor Sadiq Khan alongside disputed claims about mosques and churches.
Labour MP Wes Streeting, who co-chairs a parliamentary group on Islam, says Leave.EU is now "a far-right organisation".
Leave.EU says Britons aren't "allowed" to talk about Muslims.
"As for the Muslim issue, no-one is allowed to talk about it and won't for fear of being labelled racist by the likes of him (Wes Streeting)," a Leave.EU spokesperson told Newsbeat.
Leave.EU's tweet claimed London has "423 new mosques, 500 closed churches and 100 Sharia Courts".
The BBC's Reality Check says the claims are from "out of context" sources - scroll down to see what else they have to say.
Leave.EU was one of the groups - although not the main or official one - which campaigned for the UK to leave the European Union.
It is now actively campaigning about the Brexit negotiations.
At lunchtime on Tuesday Leave.EU sent out a tweet claiming that "British multiculturalists feed Islamic fundamentalism".
"Londonistan, built on the sad ruins of English Christianity", it said.
Labour MP Wes Streeting, who's the co-chair of a parliamentary group on Islam, told Newsbeat the tweet is "out and out racist politics".
"Leave.EU are sending out tweets that are entirely unrelated to the European referendum," he said.
"I think they're now a far-right organisation trying to stir up hatred and division between different communities."
He also accused Leave.EU of "playing with fire" - describing the tweet as a "total gift" for Islamic hate preachers trying to radicalise people against the West.
A Leave.EU spokesperson responded: "(Wes Streeting) would say that wouldn't he? It's a well-worn path by the left when they don't want to talk about an issue.
"As for the Muslim issue, no-one is allowed to talk about it and won't for fear of being labelled racist by the likes of him."
London Labour called the tweet a "disgusting example of Leave.EU using shoddy and baseless statistics on social media to peddle their racist agenda".
The photo has faced a backlash on Twitter too.
What an overtly islamophobic tweet.— Rodney Joseph Burns (@rodney1710) April 3, 2018
Analysis by Reality Check
The statistics used are based on out-of-context sources and, importantly, give no sense of time span.
They originally appeared in an article by right-wing think-tank the Gatestone Institute.
The church closures is based on a Wall Street Journal property article from 2012, which states that between 2001 and 2011, 500 former churches had been converted into flats - but this doesn't say when they closed nor does it account for any new churches or congregations that have appeared.
Research by the Brierley Consultancy says that between 2005 and 2012 alone, 700 new churches have appeared in London driven by an increase in Pentecostalism.
The 423 'new' mosques comes from an interactive map from Muslims in Britain, a tool aimed at helping Muslims find religious spaces across the UK.
This website does not claim these mosques are 'new' - we know as a fact that the East London Mosque, Finsbury Park mosque and others (which all appear on the map) were founded decades ago.
A report by the website does suggest that between 2015 and 2017, 232 new mosques had appeared across the UK. They state that the mosques vary in size and function, from formal structures to converted houses.
The 100 Sharia courts claim seems to come from a 2009 Civitas report, which actually estimated 85 across the whole of the UK. However this included online forums, not just physical courts, and the report itself admitted that the actual number was "indeterminate."
In an email to Newsbeat, Leave.EU's founder - ex-UKIP donor Arron Banks - said: "Quoting research is not racist.
"Have we become that PC (politically correct) that even mentioning the word Muslim is now banned for fear of being labelled a racist?"
When asked about the accuracy of the statistics, a Leave.EU spokesperson added: "All we have done is highlighted certain data and research - if the facts are wrong then you should take that up with those that produced the research."
Despite eventually deleting the tweet, Leave.EU posted a defence of it - saying "it's not racist to discuss these issues".
This latest tweet comes less than a week after the group was criticised by several MPs for a social media post which linked Islam to allegations of anti-Semitism in the Labour party.
The tweet suggested the party wasn't dealing with the problem because it was more focused on winning Muslim votes.
Is it any wonder that Labour can't be bothered to deal with the disgusting antisemitism in their party when they are so reliant on the votes of Britain's exploding Muslim population? It's a question of maths for these people, not justice!— Leave.EU (@LeaveEUOfficial) March 29, 2018
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