Serge Brammertz – who will step down later this month as head of the International Independent Investigation Commission (IIIC) – said he could not yet predict when the inquiry into the massive car bombing in downtown Beirut, which killed Mr. Hariri and 22 others, would be wrapped up.“Conducting an investigation is never an exact science,” he said in a briefing on the latest report of the IIIC. “The completion of the investigation will depend on the final results of several ongoing projects and on the cooperation of all States,” adding that it also relied on the willingness of additional witnesses to come forward.Mr. Brammertz, who is being succeeded as investigation chief by Daniel Bellemare of Canada, stressed that it was paramount that the IIIC continues to receive the administrative and resource support it needs to carry out its work in the months ahead.“When I am asked whether I am satisfied with the progress made so far, my answer is absolutely yes. Important results have been achieved in many areas of the investigation despite the numerous challenges the Commission has faced. Based on the progress made in recent months, I am more confident and optimistic than ever that the investigation can be concluded successfully.”Mr. Brammertz did not reveal many details about the IIIC’s findings so far, saying his Office was increasingly cautious about the release of information given that it does not want to compromise any future legal process at the planned Special Tribunal for Lebanon, being set up to deal with the Hariri killing and up to 18 other politically-related murders in the country in recent years.But he noted that, based on hundreds of interviews and examinations, investigators have been able to answer or substantially narrow the focus on many of the key questions surrounding the bombing, including the possible motive, the identity of the suicide bomber and details about the persons who conducted active surveillance on Mr. Hariri ahead of the attack.Ahmed Abu Addas, who appeared in a video claiming responsibility for the assassination, was not the suicide bomber, Mr. Brammertz said, but may still be connected to the attack.He added that investigators have gathered large amounts of evidence about the video, the Mitsubishi van in which the bomb exploded, the crime scene and many other forensic issues.Drawing on tests of DNA and teeth and other information, the IIIC “has developed one principal hypothesis” about the identity of the suicide bomber, especially the specific area of the Middle East from which the young male is thought to have originated. But more tests need to be conducted to confirm the hypothesis.Expert findings indicate the bomber was exposed “to significant quantities of a specific type of lead, possibly through proximity to military ammunition, between the ages of 16 and 20,” which could show the man was living near an area of conflict or one where weapons were regularly used, such as a military training camp.“New expert findings have provided additional information on the possible place of birth of the unidentified male, as well as further details on the location where he may have spent his childhood.”Turning to another political assassination in Lebanon, the death of the parliamentarian Antoine Ghanem in September this year following a car bombing in eastern Beirut, Mr. Brammertz said the initial findings indicated that the perpetrators were able to conduct surveillance and mobilize a vehicle-borne improvised explosive device (IED) “within a very short window of time.“This and other preliminary results in other cases suggest that the perpetrators had – and most likely still have – operational capabilities available in Beirut.”Mr. Brammertz also said that investigations so far suggest that “some operational links exist” between the various attacks being probed by the Commission. 5 December 2007The head of the United Nations probe into the assassination of former Lebanese prime minister Rafiq Hariri is “more confident and optimistic than ever that the investigation can be concluded successfully,” he told the Security Council today, explaining that his team has been able to answer many key questions regarding the February 2005 attack.