The BBC's head of newsgathering has admitted that the corporation should not have described the London rioters as "protesters" after Saturday night, when a peaceful demonstration provided the initial spark for three days of escalating disturbances across the capital.

The BBC was criticised on Tuesday for continually referring to the looters and rioters as "protesters" – three days after the peaceful protest over the death of Mark Duggan in Tottenham.

Speaking to BBC Radio 4's The Media Show, Fran Unsworth conceded that its presenters should have dropped the term earlier.

"I think it was probably OK [to use the term "protesters"] on Saturday when the whole incident started off in a peaceful protest in Tottenham," Unsworth said. "But since then I don't think we should have been using 'protesters', clearly they are looters and rioters and that's how we should have been describing them."

Unsworth said: "We try not to be too prescriptive, but yes we have said actually that they're not protesters they're clearly rioters and looters. They are more descriptive terms and we should try and be as accurately descriptive as we can be."

Unsworth confirmed that the BBC had received 62 complaints from viewers on the language issue – but pointed out that 54 of those came after it was highlighted in the Daily Telegraph.

A Telegraph leader on Tuesday claimed the BBC "stupidly insisted" on calling the rioters "protesters".

Mary Hockaday, the head of the BBC multimedia newsroom, rebutted that claim in a post on the corporation's editors' blog on Wednesday.

"It's simply not true to suggest the BBC has portrayed these events as protests," she said. "Our role as with any story is to accurately reflect what is happening – from the original protest in Tottenham on Saturday night through to the subsequent riots and looting.

"We have clearly reported the riots, looting and mayhem of the past few days. The word protest or protester may have cropped up in live fluid coverage, as has been the case with other broadcasters, but none of our audiences to any platform can have been left in any doubt that we have been reporting riots and looting."

Separately, the BBC on Wednesday apologised for a BBC News channel interview with the prominent writer and campaigner Darcus Howe, who presenter Fiona Armstrong accused of taking part in riots in the past.

During a live interview, Armstrong said: "You are not a stranger to riots yourself I understand, are you? You have taken part in them yourself."

Howe replied: "I have never taken part in a single riot. I've been part of demonstrations that ended up in a conflict.

"Stop accusing me of being a rioter and have some respect for an old West Indian negro, because you wanted for me to get abusive. You just sound idiotic – have some respect."

The BBC said in a statement: "We'd like to apologise for any offence that this interview has caused."

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