Complaints after political editor quoted source saying that attackers were of 'Muslim appearance' during Six O'Clock News

The BBC's political editor, Nick Robinson, has apologised after he quoted a source who apparently described the Woolwich attackers as being "of Muslim appearance".

The corporation received 43 complaints after Robinson used the phrase on BBC1's 6pm bulletin on Wednesday, hours after the savage machete attack that killed a serving soldier in London.

On Thursday, the BBC's political editor said he regretted his choice of words, writing on his official BBC blog: "With minutes to go before the BBC News at Six I was told by a senior Whitehall source that the incident was being treated as a suspected terrorist incident and being taken very seriously indeed.

"This information changed the news from a crime story to something of more significance. The police had, I was told, described the attackers as being 'of Muslim appearance; and shouting 'Allahu Akbar'. On air I directly quoted a senior Whitehall source saying that the police had used that description.

"That phrase 'of Muslim appearance' clearly offended some who demanded to know what it could possibly mean. Others were concerned that it was a racist generalisation."

His report on the BBC's most prominent bulletin was quickly picked up by media organisations around the world, who described it as evidence of a terrorist attack. Eyewitness reports later suggested that at least one of attackers had claimed to be retaliating because "Muslims are dying daily by British soldiers".

Robinson added: "Despite this and the fact that I was directly quoting a source I'm sorry for using a phrase that, on reflection, was both liable to be misinterpreted and to cause offence. Many Muslims were quick to condemn the attack and to distance themselves and their religion from the brutal savagery seen on the streets of Woolwich.

"The overnight protests of the English Defence League and attacks on some mosques lead some to fear the consequences for community relations. This all makes people understandably sensitive about anything which could be used to justify hostility to people on the basis of their appearance or religion."

Dozens of viewers complained on social networks following the broadcast. Hannah McGill, a film reviewer and panellist on BBC Four's Review Show, posted: "Whatever just happened, @BBCNews, it is entirely not OK for your correspondents to refer to anyone as 'of Muslim appearance'."

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