The inquiry into the killing of a former Lebanese prime minister has asked several countries to help identify the presumed suicide bomber from a tooth and other pieces of DNA, the chief investigator told the U.N. Security Council on Friday. He also spoke of the connection between the various assassinations that took place at that time. "As a result of the work done during the reporting period, the commission has strengthened its preliminary conclusions that the 14 cases were not commissioned and executed by 14 disparate and unconnected persons or groups with separate motives. The Commission anticipates that further links between these cases will be evident upon further collection of information and evidence." The Belgian former prosecutor is leading the U.N. probe into the 2005 killing of former Lebanese leader Rafik al-Hariri and 22 others in a Beirut street bombing. The investigation's current mandate runs until June 2007. Syrian U.N. Ambassador Bashar Jaafari said that Syria would co-operate to the extent possible because the uncovering of the truth would be his country's interest. warned the council against jumping to conclusions about the identity of the killers before all the evidence is in. "One of the most dangerous things that this investigation faces is the continuance of the exploitation of some parties in our region or outside it, of what happens in the investigation to jump to pre fabricated conclusions which are not based on any evidence or clear proof," said Jaafari Jaafari said investigators should prosecute anyone found to have presented false testimony. He also urged them to look into the activities of the Israeli secret services and the Israeli military during the month-long war with Lebanon's Hizbollah that ended last month. The U.N. inquiry has identified 28 pieces of human remains including a tooth recovered from the bombing site as belonging to a man thought to be in his early 20s and not of Lebanese origin, said Serge Brammertz. Brammertz called the tooth "extremely important." "Indeed, the tooth we are mentioning found on the crime scene in May is extremely important because analysing a tooth, and I will not start with too many explanations about this issue, but based on a tooth we can not only identify the age of somebody but also the regional origin," he said. In a report released this week, he said it showed a "distinguishing mark ... rarely seen among people from Lebanon." Brammertz also said that the person's DNA was being compared with existing DNA databases in several countries. He declined to name the countries. U.S. Ambassador to the U.N. John Bolton said it appeared clear the U.N. team still had Syria in its sights given the conclusions and some of the specifics that Brammertz presented in the Security Council meeting. And although Brammertz did say that the Syrians had co-operated with the investigation, Bolton felt they could do more. "If the Syrians would spend more time cooperating with the commission and less time making suggestions, we might move this along more quickly," said Bolton. Hariri, who became a critic of Syria's decades-long domination of Lebanon shortly before his death, was killed by a huge bomb on Feb. 14, 2005, as his motorcade sped past. The attack took place after he accused Syria of meddling in Lebanese politics. Mass street protests followed and Lebanese opposition politicians blamed Damascus for his death, although Syria has repeatedly denied any involvement in the killing.