Two men accused of performing female genital mutilation in Birmingham have been released from police bail after the Crown Prosecution Service expressed doubts over evidence obtained by a newspaper.

Dentist Dr Omar Sheikh Mohammed Addow, 55, and GP Dr Ali Mao-Aweys, 61, were arrested after an undercover investigation by the Sunday Times was published in April.

The article was bylined Mazher Mahmood, the leading investigative reporter at the paper who has been nicknamed the "fake sheikh" for his undercover reporting, and Eleanor Mills.

The two men were approached by an undercover reporter and both allegedly agreed to perform genital mutilation on two girls aged 10 and 13.

The News International paper also claimed to have recorded Addow describing how the operation could be performed and agreeing to do it for £750.

After reviewing all the evidence obtained by West Midlands Police, the CPS decided that the two men should be released. It cited inconsistencies between the undercover reporter's statements and how she "consistently failed" to sign off her statement to the police.

The CPS said the article failed to mention that during the covert recordings the two men refused to cooperate with the woman's request for genital mutilation.

Harry Ireland, Chief Crown Prosecutor for the West Midlands, said: "Having carefully reviewed the evidence obtained by the police, I have decided there should be no further action against either of these two men. The case has been reviewed according to the Code for Crown Prosecutors and there is insufficient evidence for a realistic prospect of conviction.

"The main evidence in this case is from the undercover journalist or agent but she has consistently failed to sign her draft statement for the police despite being given every opportunity to do so over the past five months.

"I also have concerns over discrepancies between her draft statement and the evidence from the covert recordings. For example, at one stage, the covert recordings record the doctors refusing to help the woman with her request.

Search failed to provide evidence

"I am also troubled by the fact that the covert recordings disclose a time gap which is insufficiently accounted for when the undercover journalist or agent apparently went with one of the doctors from the surgery to his home. Unless there is a very compelling explanation for this, the covert evidence is very unlikely to be admissible in evidence. That explanation has not been forthcoming."

The CPS added that a search of the suspects' homes, computers and phones failed to provide any evidence that they were involved in FGM.

A spokesperson from The Sunday Times said: "The intention of this investigation was to highlight the alarming practice of female genital mutilation. The article was not accusing the doctors of committing a crime, but of being willing to consider aiding FGM. We stand by our investigation and contest the state

The article said that as many as 100,000 women have undergone the procedure in the UK, some of them as young as 10 years old.

Sometimes known as "cutting", the procedure is traditionally carried out for cultural reasons and is widespread across parts of Africa.

No one in the UK has ever been prosecuted for involvement in female circumcision.

Det Chief Insp Garry Billing said: "Following the receipt of allegations that female genital mutilation was being offered in Birmingham earlier this year, two men, aged 55 and 61, were arrested on suspicion of offences contrary to the Female Genital Mutilation Act 2003.

"A comprehensive investigation was launched by detectives and all available evidence was presented to the Crown Prosecution Service which they examined and have decided that in this particular instance this does not merit a prosecution.

"We note the decision of the CPS and the two men have now been released from police bail without charge."