Updated

One of Kofi Annan's (search) closest friends and colleagues is now in the crosshairs of Oil-for-Food investigators.

Members of Paul Volcker's Independent Inquiry Committee on Tuesday revealed that Iqbal Riza (search), the former chief of staff, shredded thousands of documents that might have shed light on Annan's involvement in the Oil-for-Food (search) scandal and that Riza acted in contravention of one of his own directives.

Tuesday's report said Annan did not improperly use his influence to help the Swiss-based Cotecna (search) contracting firm win an Iraq Oil-for-Food contract, even though his son, Kojo Annan (search), worked for the company. The report did say, however, that Annan didn't do enough to investigate the connections between his son, Cotecna and Oil-for-Food, and that the lack of further oversight could have prevented some of the gross mismanagement of the program.

Read the full report by clicking here (pdf).

The IIC found that Riza allowed documents of potential relevance to the Volcker investigation to be shredded by his staff, even though he was aware of the ongoing probe.

On April 12, 2004, as the Oil-for-Food scandal gathered steam, Riza sent letters to the heads of the nine U.N.-related agencies that administered Oil-for-Food in northern Iraq, suggesting they cooperate with the investigation and "take all necessary steps to collect, preserve and secure all files, records and documents" relating to the program.

Then, on April 21, the U.N. Security Council approved a full investigation of the program. The next day, Riza ordered the shredding of three year's worth of documents in his office. According to the IIC, the shredding continued until the week of Dec. 7 — more than seven months after Annan, on June 1, ordered all U.N. employees and staff members "not to destroy or remove any documents related to the Oil-for-Food programme that are in their possession or under their control, and to not instruct or allow anyone else to destroy or remove such documents."

According to the Volcker report, Riza's assistant who personally shredded the documents told the IIC that after getting the thumbs-up from Riza to do the deed in April 2004, the two never talked about the matter again and she didn't update him on the status of the ongoing shredding until it was finished in December.

The report says Riza didn't tell the IIC that he approved the destruction of three years of his documents when first interviewed in the investigation on Dec. 20, 2004.

Two days later, Riza called the IIC to say that some documents couldn't be located because they had been destroyed. He then produced a copy of his memorandum authorizing the shredding. Riza claimed he was aware of the investigation when he OK'd the shredding, but that he "did not connect" those files to those that may be relevant to the Oil-for-Food investigation. He thought the files in question were simply copies of records already stored in a central U.N. system.

But Volcker's committee found evidence that proved otherwise.

For example, a "confidential note" from Riza to Joseph Connor (search) — the undersecretary-general in charge of the Office of Internal Oversight Services who also was fingered in the report — requesting his review of the Cotecna matter was on Riza's computer and presumably should have been in his now-destroyed files from 1999. But despite Riza's claims that the destroyed chronological records, known as "chron" files, were just duplicates, that specific note to Connor hasn't been found in the U.N. central records unit.

"The committee does not find persuasive Mr. Riza's suggestion that his 'chron' files were only duplicates of files maintained elsewhere at the United Nations," the IIC report states.

Investigators say, therefore, that the shredding incidents are deeply suspicious.

"My own reaction was one of deep concern and I think that's what any reasonable person would feel," Justice Richard Goldstone of the IIC told FOX News.

Asked if the evidence — whether or not it did point more of a finger at Annan in the controversy — was lost forever, Goldstone replied: "Yes, that's correct."

When asked what, if any, action he would take against those U.N. officials accused of various actions in the report, Annan said Tuesday: "These findings raise different and complex issues in each case, which I need to study carefully before deciding what steps need to be taken."

FOX News called Riza at his home and asked how he intends to respond to the report.

"I would like to clear my name. I will be deciding in the next week how I go about doing that," Riza said.

Riza was asked by FOX News if he was concerned that Annan seemed happy to let others, including Riza and Annan's son Kojo, take the blame for any wrongdoing in the scandal.

"I do not want to enter that discussion right now," Riza responded.

Another item that interests investigators is why, after Riza resigned as chief of staff earlier this year, Annan gave him a $1-a-year contract keeping him as a U.N. employee, thereby ensuring he had diplomatic immunity.

Volcker's panel was commissioned by Annan to investigate the $64 billion program, which aimed at relieving Iraqi civilians from some effects of the sanctions imposed on Iraq after Saddam Hussein's invasion of Kuwait. Saddam allegedly gave former government officials, activists, journalists and U.N. officials vouchers for Iraqi oil that could be resold. Investigators claim the former Iraqi regime may have illegally made more than $21 billion by cheating the program and through other sanctions-busting schemes.

FOXNews.com's Liza Porteus contributed to this report.

Click on the video box above for a complete report by FOX News' Jonathan Hunt.