Record numbers have complained to the press industry watchdog after The Sun made a claim that one fifth of British Muslims had “sympathy for jihadis”.

The tabloid’s claim, in a front page headline, was based on a survey of Muslim and non-Muslim opinions commissioned in the wake of the Paris attacks. The study found that 19 per cent of Muslims expressed at least “some sympathy” with young Muslims who had left the UK to join fighters in Syria.

But the newspaper’s interpretation of the poll data was called into question by numerous critics who noted that an earlier survey for Sky News had shown that more than 30 per cent of non-Muslims had shown a degree of sympathy with young Muslims fighting in Syria.

The Sun front page provoked an unprecedented wave of complaints to the Independent Press Standards Organisation (IPSO). The watchdog had recorded 450 complaints, the most for a story published since it opened for business on 8 September 2014.

The number of complaints was greater than the 400 received over Sun columnist Katie Hopkins’s description of migrants as “cockroaches” in an article in April. It also eclipsed the 300 protests to IPSO over a drawing by Daily Mail cartoonist Mac last week, in which he depicted Muslim migrants crossing the borders of Europe in the company of rats.

Despite its headline, The Sun’s report contained the acknowledgement that “a clear majority of the 2.7 million Brits who follow Islam are moderate”. It also noted that since the Sky News survey in March, the percentage of Muslims expressing any sympathy for the UK Muslim fighters in Syria had fallen from 28 per cent. “The number who have no sympathy at all for jihadis has also risen from 61 per cent in March to 71 per cent today.”

The tabloid’s headline provoked a furious response from the Muslim Council of Britain which accused the paper of “sensationalising” the findings. Dr Shuja Shafi, Secretary General of the Muslim Council of Britain (MCB), said: “Many Muslims will find this poll hard to believe. The vast majority of the almost 3 million British Muslims abhor terrorism. Poll after poll attest to this, as do the many surveys showing how almost all British Muslims would report someone from the Muslim community to the police, if they knew they were planning an act of violence.” Dr Shafi said one person “harbouring sympathy” for the ISIS “death cult” was “one too many”.

But he added: “Dubious headlines as that printed today in The Sun does not help matters. The grand strategy of Daesh is to divide our communities and stoke fear between communities. We should not play their game.”

The Sun's controversial front page

Other critics noted that “sympathy” was an ambiguous term in the context and that the word “jihadis” had appeared in The Sun’s headline but not in its question. Nor had the question – in a telephone poll also by Survation - specified that fighters were joining ISIS.

The front page story was linked to a column piece by former Sun editor Kelvin MacKenzie, headlined “This shocking poll means we must shut door on young Muslim migrants.”

The paper claimed last night it had revealed “an undeniable truth” in its poll.