A book documenting paramilitary threats went missing from Omagh RUC station during the height of the inquiry into how police handled the Omagh bombing investigation, it has emerged.
This latest embarrassing revelation comes as Sir Ronnie Flanagan, Chief Constable of the Police Service of Northern Ireland (PSNI), prepares to present his response to the Police Ombudsman Mrs Nuala O'Loan's devastating criticisms of his leadership and her findings that the RUC mishandled the bomb investigation.
The disappearance of the book was confirmed in Mrs O'Loan's full report to the Northern Secretary Dr John Reid last month, but not recorded in the summary she released to the families and press, sources disclosed.
Members of the Police Ombudsman's office who were investigating the RUC inquiry into the bombing asked to see the book in September last year, but were told it had gone missing.
It is believed it disappeared in August 2000 when the RUC was carrying out its internal review of how police dealt with the inquiry into the August 1998 "Real IRA" bombing, which claimed the lives of 29 people and unborn twins.
The Police Ombudsman wished to examine the book to establish how many threats had been recorded previously, to assess their importance and to study what action, if any, had been ordered as a response.
Mr Michael Gallagher, of the Omagh victims' group, said he was "flabbergasted" at this latest disclosure.
"It seems extraordinary that a book of this importance can disappear in a controlled environment of a police station."
The SDLP MLA and Policing Board member Mr Joe Byrne said the revelation was disturbing. "At its worst it is further confirmation of inadequate management practices within the police. It gives rise to questions as to what certain elements within the police have done or failed to do in relation to Omagh," he added.
The Chief Constable was due to circulate his response to the Ombudsman's report to Dr Reid, the 19-member Policing Board and Mrs O'Loan yesterday but delayed doing so until later today or possibly tomorrow.
He is to brief the Omagh families on Thursday and then release his report to the media.
A security source said that Sir Ronnie would also deal with the issue of the missing book on Thursday.
The Irish Times also learned last night that efforts were made to persuade Sir Ronnie to temper his response so that neither the PSNI nor the Police Ombudsman's office would be undermined by this bitter dispute between him and Mrs O'Loan.
The Northern Ireland Office at a very senior level and some members of the Policing Board are understood to have contacted Sir Ronnie, urging him to be particularly mindful of what was at stake.
"The point was made that if he gets the tone and content right that he could do a lot of good for the police and the Ombudsman's office but that if he gets it wrong everybody could be damaged, including himself," said one source.
Sources last night said that Sir Ronnie remained "resolutely determined" to rebut Mrs O'Loan's criticisms.
