IPSO – the Independent Press Standards Organisation – is understood to be investigating a headline over a Scottish Daily Express story about the All Under One Banner independence march in Glasgow earlier this month.

The headline alleged that thousands of Scottish nationalists had clashed with pro-union activists during the event, which prompted anger on social media.

Twitter user @RiddlywalkerB said yesterday they had received an email from IPSO, which read: “Thank you for your email. After an initial review, we have determined that your complaint falls within IPSO’s remit and raises a possible breach of the Editors’ Code of Practice. We have received over 200 complaints regarding this matter.”

They said the email was related to a complaint they made against the Express headline.

Mysteriously, the link to the original Express story delivers a 404 “page missing” message, while a Twitter search reveals a new story suggesting that Unionists gatecrashed the independence march.

A spokesperson for IPSO told The National: “I can confirm that we have received 216 complaints about this article, mostly under Clause 1 (Accuracy) of the Editors’ Code.”