Four former FBI agents once charged with investigating the Oklahoma City bombing told “60 Minutes II” last night they know of more evidence in the case ignored or mishandled by the government.

One agent, Rick Ojeda, who received a commendation for his work on the case, says evidence he obtained that might have helped convicted bomber Timothy McVeigh’s defense was either ignored or not properly documented by the FBI.

“I started thinking and I started going back and checking to see if some information that I provided had ever been mentioned at the trial, and I talked to a couple of agents that worked the case and asked them about leads that I had done – were they ever brought up,” said Ojeda. “I even asked them to check to see if some of the (documents) that I had mentioned had ever been turned over and they couldn’t find them and so I started to wonder if the stuff had been withheld or just lost, which was common.”

Veteran FBI agent Jim Volz was on duty April 19, 1995, the day the Alfred P. Murrah Federal Building was destroyed. He reviewed the FBI’s internal documents on the bombing, including interview notes, witness statements, sightings and tips.

“It’s extremely surprising to me that these documents all of a sudden show up,” he said. “There’s no reason for it unless there is negligence.”

Dan Vogel, the FBI’s communications office in Oklahoma City during the bombing probe accused the agency of “obstructing justice.”

“There was a cultural problem in the FBI that needed to be addressed, otherwise it is going to destroy itself,” said Vogel. “You see, the FBI is made up of a lot of very fine, dedicated people. And these people deserve better, and these recent revelations where we have a man scheduled for execution and all of a sudden we find documents that haven’t been turned over to the defense attorneys or to the prosecution a week before the execution, that really made up my mind. After that there was no question in my mind that I needed to come here today and do whatever I could to – to try to get this changed.”

McVeigh is scheduled for execution June 11. His date with death was extended by Attorney General John Ashcroft earlier this month after the disclosure by the FBI about the evidence withheld.

McVeigh’s attorney, Rob Nigh, pledges to use the information from the FBI agents “to change the course of this case in the near future.”

“These agents have indicated that there is at least a possibility of misconduct rising to the level of criminal misconduct in Tim McVeigh’s defense,” he said. “The importance of this information cannot be overstated. … I was absolutely overwhelmed.”

Some 4,034 pages of evidence have just been turned over to McVeigh’s defense in the last two weeks. Officially, the FBI blames computer and record-keeping blunders for the lapse and claims most of the documents were not material to the case.

Ashcroft, meanwhile, reiterated yesterday that the new evidence would not result in a further delay of McVeigh’s execution.

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