A row has blown up after police seized the confidential mobile phone records of a newspaper reporter in a bid to discover his sources.

Civil liberties groups and the Society of Editors last night said they were outraged by the almost unprecedented move.

But police defended their actions - and said they were fully "justified".

Det Supt Roy Lambert, Suffolk's most senior detective, obtained private mobile phone records of news reporter Mark Bulstrode.

He acted after the East Anglian Daily Times journalist approached the force with information about the reopening of an historic investigation that was not public knowledge.

The EADT agreed not to run anything on the inquiry because of its sensitive nature.

But Det Supt Lambert was concerned how Mark found out about the case - and as a result got hold of his phone records.

Officers are permitted to obtain such information if they believe a criminal offence has taken place.

But no criminal charges have resulted from the inquiry.

The force admitted it held records of telephone calls made by the experienced reporter after a request was made under the Data Protection Act.

This can be used by any individual to find out what information is held about them by organisations and authorities.

But when police first responded to the request, in June, they refused to confirm or deny whether they held any of the records.

It was only after the request was resubmitted, and the force was told the Information Commissioner had been contacted for advice in relation to the matter, that a print-out of the phone records held were handed over - seven months after the initial request was put in.

A spokesman for Suffolk Police said the action was not directed at the EADT.

He said it was taken "to establish if any officer was unlawfully disclosing information which could have resulted in them perverting the course of justice or committing an offence of misconduct in public office.

"There was concern that the disclosure of information could have jeopardised an investigation into a serious crime, potentially resulting in an offender evading justice."

He said the application to obtain the phone records would have gone through a "rigorous process" within the force to ensure it was justified.

But no criminal charges have resulted from the investigation - although a serving police employee has been given "words of advice", the spokesman said.

Last night EADT editor Terry Hunt said: "I find this very disturbing.

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