Worried child benefit claimants are signing up to online credit monitoring in droves to help to protect their finances after the admission yesterday by HM Revenue & Customs that it had misplaced the personal details of 25 million people.

It is feared that if the information, which includes names, addresses, national insurance numbers and bank details, falls into the wrong hands, millions could be at risk of identity fraud.

The three credit reference agencies, Callcredit, Experian and Equifax, say that there has been a sharp increase in the number of people contacting them.

A spokeswoman from Equifax said: "We have been inundated with calls."

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Experian said that there had been an 85 per cent increase in the number of people signing up for its online monitoring service. The service is free for a month, but then costs £6.99 a month.

Callcredit said that the number of phone inquiries had trebled so far today.

It has also seen an increase in online traffic.

Some people may not realise that they have fallen victim to ID fraud for months, as fraudsters can use their personal details to set up loans or mobile phone contracts in their name.

Experian said that the average time it took for victims of ID fraud to realise was 16 months.

But by ordering regular credit reports, or signing up for an online credit monitoring service, consumers will be alerted every time an application for credit is made in their name.

Worried banks customers have also been contacting their banks for reassurance.

Halifax, one of the UK's biggest banks, said that there had been an "upturn" in calls.

A spokesman said: "The pattern of calls is the same as you would expect on a Wednesday, but the volume has been a bit higher than we would expect."

Current account-holders have been warned to be vigilant and to check their statements regularly.

The Halifax spokesman said: "Banks are always monitoring accounts for unusual activity, but banks can only go on what they have seen already.

"The person who is best placed to spot any fraudulent activity is the customer."

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