This is major. The FBI has begun a new probe into the testimony of former FBI crime lab director Steven Burmeister at the OKC bombing trial of Timothy McVeigh. New documents, undisclosed to the defense, show Burmeister may have lied about the results of critical lab tests at the trial.

The FBI internal affairs office is investigating the crime lab's chief of scientific analysis about his conduct in the Oklahoma City bombing case, according to people familiar with the investigation.

The Associated Press reported last spring that a transcript of a Justice Department interview showed that FBI scientific analysis unit chief Steven Burmeister initially had alleged in 1995 that his lab colleagues performed shoddy work in Timothy McVeigh's case, but then retracted several statements before appearing as a prosecution witness at the trial.

AP also reported that lawyers for some FBI lab employees sent a letter to Attorney General John Ashcroft in 2001, just days before McVeigh was executed for the April 1995 bombing, alleging Burmeister may have been pressured to give false testimony in the case. No action was taken and the allegation was never divulged to McVeigh's lawyers.

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