The BBC has apologised after an interviewee described Maajid Nawaz, the founder of anti-extremist think-tank Quilliam, as a “hate preacher”.

The live harangue against Maajid Nawaz came from the chairman of the Islamic Human Rights Commission, which convened Sunday’s bitterly controversial al-Quds march through central London.

Speaking on BBC TV in the hours after a van was driven at worshippers leaving the mosque, leading to the death of one person and the injuries of several more, Massoud Shadjareh said his organisation had repeatedly warned that an attack against Muslims could take place. “It was bound to happen sooner or later”, he said. “We warned the Metropolitan Police, the Mayor of London, of the level of hatred on a daily basis, it was very dangerous and it could lead to something like this.”

But Mr Shadjareh then went on to make specific allegations against “hate preachers” on radio and media, naming Maajid Nawaz, the outspoken Sun columnist Katie Hopkins and the Spectator writer Douglas Murray, as people who were “bombarding” audiences with “hatred of the Muslim community and indeed mainstream Islam. This cannot go on”, he said

On BBC News on Tuesday, the Broadcaster apologised to Nawaz for  airing the remarks. The newsreader said: “At this time yesterday, we interviewed live a contributor, who expressed the view that Maajid Nawaz was a “hate preacher”. Mr Nawaz is founding chairman of the Quilliam Foundation, which described itself as one of the world’s leading counter-extremism organisations.

“We would like to make clear that we were unaware that Mr Nawaz would be named in this way, and would like to apologise to Mr Nawaz.”

Following the apology, Maajid took to twitter to give “thanks & gratitude to my lawyer Mark Lewis for sorting that one out.”

Last week Mr Nawaz, who has consistently denounced extremism from all areas of British society, bitterly condemned the forthcoming al-Quds demonstration in a column for the Jewish News. Noting that the Islamic Human Rights Commission had claimed that any Hizbollah flags carried at the demonstration would represent only the political wing of the organisation — a distinction not made by Hizbollah itself — Mr Nawaz deplored the demonstration and its intention.

He urged action against the organisers, writing: “Why must ordinary everyday British Muslims be expected to bear the brunt of public anger because of indefensible political correctness of our institutions, politicians and bureaucrats?”

Mr Nawaz posted a message on social media, “Journalists, take note”, as a warning to the BBC as to who Massoud Shadjareh is, after a number of people questioned Mr Shadjareh’s comments.