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The United Nations offered few comments Monday on an exclusive CBC News story about the 2005 killing of former Lebanese prime minister Rafik Hariri.

The CBC investigation, relying on interviews with multiple sources within a UN inquiry into the killing, along with some of the inquiry's own records, found examples of timidity, bureaucratic inertia, and incompetence bordering on gross negligence in the UN probe.

One of the records lays out networks of cellphones linked to the Hariri murder. The networks were uncovered by murdered Lebanese police officer Capt. Wissam Eid and UN investigators, and they provide evidence that Hariri's assassins had ties to the Lebanese militant group Hezbollah.

"I … don’t have any comment on the substance of those documents," UN spokesman Farhan Haq said during a daily briefing at UN headquarters in New York City.

Haq said he can't confirm the authenticity of any of the documents obtained by CBC News, adding that if they are UN documents they are privileged documents that should not be "disclosed to a third party, copied or used without the consent of the United Nations, which had not been given in this case."

He added: "We had requested CBC to contact us with information regarding the documents, so that we could assess them."

The original UN probe into Hariri's murder — the UN International Independent Investigation Commission — has subsequently been transformed into the Special Tribunal for Lebanon, residing in The Hague, where Canadian Daniel Bellemare is now its chief prosecutor.

U.S. State Department spokesman P.J. Crowley called the work of the Special Tribunal for Lebanon "critically important to Lebanon's future.

"Lebanon needs to end this era of impunity, which has afflicted it for years, if not decades. And we support the work of the tribunal and we look forward to completion of its investigation," Crowley said.