The BBC added its own soundtrack of babies gurgling to a news report about the birth of quintuplets, the corporation admitted.

BBC News was at the centre of another “fakery” allegation after admitting that producers manipulated the soundtrack of footage received from John Radcliffe Hospital in Oxford.

A 29 year-old Russian woman gave birth to the quintuplets last Saturday, 14 weeks early. They ranged in weight from 1lb 13oz to 2lb 2oz after being delivered by Caesarean section by a team of 18 doctors and nurses. The babies were the first quintuplets born in Britain for five years.

The hospital said that it distributed footage of the women, the father and the infants to news organisations after receiving a number of requests. But the footage had no sound.

Other broadcasters ran the clips with a reporter’s voiceover. But when the story ran on BBC bulletins the babies were “crying”, even though they were connected to respirators.

The “enhancement” was exposed after the BBC had promised greater transparency following a series of scandals. The BBC said that it was a mistake for Newsnight to have shown footage of Gordon Brown out of sequence in a report in July.

The BBC admitted that it had altered the soundtrack. A spokesman said: “We received the film without sound and on reflection, we should have kept it that way.” The BBC would not disclose the source of the crying.

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