The government scientist has died in Maryland from suicide, just as the Justice Department was about to file criminal charges against him for the attacks, the Los Angeles Times reported.

Bruce Ivins, 62, who helped the FBI analyze samples from the 2001 anthrax attacks had been informed of his prosecution, said insiders.

Ivins, who for the past 18 years worked at the government's elite biodefense research laboratories at Fort Detrick, Md., had played a central role in research to improve anthrax vaccines by preparing anthrax formulations used in experiments on animals.

A skilled microbiologist, Ivins also had helped the FBI analyze the powdery material recovered from one of the anthrax-tainted envelopes sent to a U.S. senator's office in Washington, D.C.

Ivins died Tuesday at Frederick Memorial Hospital after having ingested a massive dose of prescription Tylenol mixed with codeine, said a friend and colleague who declined to be identified out of concern, he said, that he would be harassed by the FBI.