The Home Office has said that it will provide answers next week to freedom of information requests submitted in February about the leaking to the media of details of an important antiterrorism operation.

Government departments are supposed to answer requests entered under the Freedom of Information (FoI) Act within 20 working days, but officials at the Home Office have twice delayed their response to the pressure group Liberty, saying they needed more time.

Suspicion about the source of the leaks – condemned by Scotland Yard’s antiterrorism chief – has fallen on ministerial aides at the Home Office and 10 Downing Street.

At the time of the operation in January, which led to a number of arrests in Birmingham, the Home Office was fighting to contain criticism of its record on jail overcrowding.

John Reid, the Home Secretary, has denied that any of his special advisers briefed reporters on operational matters. The Prime Minister’s official spokesman has said that if people had evidence about leaks they should come forward with it.

Pressure is continuing for a police investigation into whether the leaks amounted to a breach of the Official Secrets Act. Section 4 of the Act outlaws the release by public officials of information that “impedes the prevention or detection of offences or the apprehension or prosecution of suspected offenders”.

Jack Straw, the Leader of the Commons and a former Home Secretary, said that a police inquiry was the appropriate response to allegations about the source of the leaks.

He told MPs: “These are very serious allegations and I agree with those who say that if they are that serious then they should be investigated by the police and not by a conventional leak inquiry.”

Deputy Assistant Commissioner Peter Clarke, head of Scotland Yard’s Counter-Terrorism Command, said in a lecture this week that the leakers were “beneath contempt” and that their actions had jeopardised the police operation.

Mr Clarke is angry that some media organisations were told in advance about the raids and that details of an alleged plot to kidnap and murder a soldier were leaked before any of the nine men arrested were interviewed.

He has long been concerned about the leaking of information about antiterrorism investigations. Almost every inquiry conducted by his team since the 9/11 attacks has been affected by disclosures to the media.

Five possible sources would have to be examined by any inquiry. In Whitehall, the Home Office and No 10 were made aware of the antiterrorist operation before the arrests. Officers at the Metropolitan and West Midlands police forces were directly involved in the operation, as was MI5.

Nick Clegg, the Liberal Democrats’ home affairs spokesman, has asked the Association of Chief Police Officers to recommend a force unconnected to the antiterrorism operation to conduct an investigation.

Mr Reid’s firm denials of the involvement of his advisers were made in letters to Shami Chakrabati, the director of Liberty, and Dominic Grieve, the Shadow Attorney-General.

Writing to Ms Chakrabati after she lodged her FoI request, he assured her “that my special advisers did not brief the media on operational matters, on or off the record, and it is not their practice to do so”. He answered Mr Grieve in similar terms.

Ms Chakrabarti said: “Secret off-the-record antiterror briefings not only heighten public fear but also undermine police operations, prejudice fair trials and isolate communities who could provide key intelligence.”

There was also “grave danger of party politics trumping public safety considerations if political staff do indeed play a role in off-the-record media briefings during these antiterror operations”.

Nine men were arrested during the raids in Birmingham. Six have been charged with terrorist offences and three released without charge.

The tip-off

— Deputy Assistant Commissioner Peter Clarke said he was concerned about “the deliberate leaking of highly sensitive operational intelligence, often classified, and the unauthorised release of which can be a criminal offence”

— Media organisations in London and Birmingham were tipped off the night before that antiterrorist raids were to take place in Birmingham in the early hours of January 31

— Within hours of the arrests several media outlets were reporting that the operation concerned an alleged plot to kidnap and behead a British soldier, probably a Muslim, home on leave

Source: Times database

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