Theresa May has been challenged over claims the Tories are "turning a blind eye" to Islamophobia within its ranks after party bosses failed to respond to calls for a probe into allegations of prejudice.
The Muslim Council of Britain (MCB), which represents more than 500 mosques, schools and organisations, has written a second letter to party chairman Brandon Lewis after it received no formal response to demands for an investigation last month.
The Independent revealed last month that the MCB had demanded a full audit to tackle “more than weekly occurrences of Islamophobia from candidates and representatives of the party”, citing offensive tweets and accusations of links to far-right groups.
MCB general secretary Harun Khan said victims of Islamophobia were concerned that voicing their complaints was "political suicide" and urged the party to root out abuse among its members.
When challenged on the issue at prime minister's questions, Ms May said the party was taking action, adding: "Anti-Muslim discrimination is wrong. There is no place for it in our society."
In a new letter, Mr Khan said: "Since we last wrote to you, other individuals have shared with us their stories of experiencing Islamophobia.
"They are worried about taking their concerns to your party because it would be 'political suicide' or might endanger their relationship with their local MP.
"This is a sad state of affairs for our democracy and we hope they can be taken up in an independent inquiry."
He referred to allegations, reported by The Independent, that one party member was told he was "not welcome" in the Conservatives, while another was allegedly told he looked "too Muslim".
Another complaint said five BME Tory party members were seated on a single table at the back of the room at a Conservative association dinner.
The MCB welcomed "positive steps" including Ms May's visit to a mosque to mark the anniversary of the Grenfell Tower fire and an article in which Mr Lewis promised to "stamp out anti-Muslim abuse or discrimination" within the party.
But Mr Khan added: "It is unclear how these statements and warm words align with the apparent tolerance for Islamophobia detailed here.
"We cannot have an approach where you are hoping that the issue would magically go away so that (you) could avoid a bruising inquiry into anti-Muslim prejudice."
Labour MP Afzhal Khan asked Ms May if the Tories were "in denial about Islamophobia" during prime minister's questions.
She replied: "Anti-Muslim discrimination is wrong. There is no place for it in our society.
"That's why, when I was home secretary, I required the police to specifically record anti-Muslim hate crime, so that we could understand better what was happening and better tackle the issue.
"Within the party, we've introduced a new code of conduct ... we investigate any allegations of Islamophobia that are made relating to members of the party.
"Those are investigated, action is taken, and in some cases members have been suspended or expelled from the party as a result."
The MCB's initial letter raised concerns about Zac Goldsmith's campaign for the London mayoralty and the social media activities of MP Bob Blackman, as well as a string of Tory councillors and candidates suspended over allegedly Islamophobic comments.
It led to a spat between the party's two most prominent Muslim figures, as former minister Baroness Warsi accused home secretary Sajid Javid of "shooting the messenger" after he said the MCB did not represent the majority of British Muslims.
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