Northern Ireland's Police Ombudsman has launched an official inquiry into the alleged misconduct of two of the key prosecution witnesses in the trial of the man accused of the Omagh bombing.
Sean Hoey, from Jonesborough in south Armagh, faces 56 charges, including the murders of the 29 people and two unborn babies who died in the Real IRA bombing in Omagh in 1998.
During his trial in Belfast, which is still ongoing, two prosecution witnesses, Fiona Cooper, a forensic scientist, and PSNI Detective Chief Inspector Philip Marshall, admitted they had changed their original statements in relation to alleged forensic evidence against Sean Hoey.
Much of the prosecution case in the Omagh bomb trial is based on forensic evidence.
A lawyer for Mr Hoey accused the witnesses of beefing up their evidence, while the trial judge criticised the pair, and said there should be an immediate inquiry into their behaviour.
A spokesman for the Police Ombudsman confirmed that Nuala O'Loan has begun a full investigation and her staff are studying court transcripts of all the related evidence.
It is thought that later she may want to speak to the two witnesses, and the trial judge, Mr Justice Weir.
The trial is expected to end next week. Judgment is likely to be reserved.
