The U.N. prosecutor investigating the 2005 assassination of former Lebanese Prime Minister Rafiq Hariri told the Security Council on Wednesday that his probe continues to make progress and asked the council to extend the investigation s mandate beyond June. The investigation made significant progress in several areas by further developing crime-scene leads, expanding the forms of evidence relating to the perpetrators, and building the linkage and context aspects of the case, prosecutor Serge Brammertz told the council in an open briefing. Brammertz listed some confirmations determined by the probe, including that the single blast that killed Hariri and 22 others was most likely from a device detonated from a van above ground and that the geographic origin of the bomber, based on data determined at the crime scene, was from outside Lebanon. The motive for killing Hariri was political, Brammertz said. One factor that influenced the murders included the enforcement of Security Council Resolution 1559, which sought to end Syrian military and intelligence influence in Lebanon Brammertz also cited Hariri s interactions with other political parties and leaders in Lebanon and Syria, the term extension for current President Emile Lahoud, and the preparation of parliamentary elections that were scheduled for May 2005. After the meeting, French Ambassador Jean-Marc de la Sabliere told reporters that he plans to introduce a draft resolution for the extension of the Hariri probe mandate, which is scheduled to expire in June. He said consensus by council members on this issue should not be problematic. Lebanese Prime Minister Fuad Siniora requested a one-year extension in a letter to U.N. Secretary-General Ban Ki-moon last month, saying in a letter that the Lebanese government hopes that Commissioner Serge Brammertz, who is doing a highly professional job at the head of the commission, will continue in the exercise of his duties during the coming period. Responding to a reporter s question, Brammertz would not confirm that he would be staying on throughout the one-year extension, if it is renewed.