WASHINGTON (Reuters) - A U.S. Army scientist who apparently committed suicide this week was close to being charged in connection with a series of deadly anthrax attacks in 2001, federal law enforcement officials said on Friday.

Bruce Ivins at a 2003 awards ceremony. A U.S. Army scientist who apparently committed suicide this week was close to being charged in connection with a series of deadly anthrax attacks in 2001, federal law enforcement officials said on Friday. REUTERS/USAMRIID/Handout

They said Bruce Ivins, 62, who worked for the last 18 years at government biodefense research laboratories at nearby Fort Detrick, Maryland, took an overdose of painkillers over the weekend and died on Tuesday in an apparent suicide.

A lawyer representing Ivins said the scientist had fully cooperated with the government’s anthrax investigation for six years, that he was innocent and they would have established that at trial.

“We are saddened by his death and disappointed that we will not have the opportunity to defend his good name and reputation in a court of law,” attorney Paul Kemp said in a statement.

“The relentless pressure of accusation and innuendo takes its toll in different ways on different people, as has already been seen in this investigation. In Dr. Ivins’ case, it led to his untimely death.”

The finely powdered anthrax was sent through the mail to media organizations and politicians shortly after the September 11 attacks by al Qaeda militants in 2001.

The anthrax mailings killed five people and sickened 17, shut down a Senate office building and spread fear of further biological attacks among Americans already reeling from September 11.

The only deadly biological attack to take place on U.S. soil, it severely disrupted the national postal service, forcing billions of dollars in changes to its operations and turned ordinary envelopes into something to be feared.

The law enforcement officials said the death of Ivins could lead to the end of the FBI’s long-running and much-criticized criminal investigation.

Earlier, suspicion cantered on another government scientist, Steven Hatfill, but he was not charged and the government agreed in June to pay him $5.85 million to drop his lawsuit against the Justice Department.

SKILLED MICROBIOLOGIST

The Los Angeles Times said Ivins had been informed of his impending prosecution shortly before his death.

Viewed as a skilled microbiologist, Ivins helped the FBI analyze materials recovered from one of the anthrax-tainted envelopes sent to a senator’s office in Washington, the newspaper reported.

The Justice Department, the FBI and U.S. Postal Inspection Service said in a brief statement that “substantial progress has been made in the investigation,” but declined to give details now.

Court documents detailing the evidence against Ivins have yet to be unsealed, and law enforcement officials said they were briefing victims and families of the victims as well as members of Congress.

In 2002, Hatfill, who worked in the same laboratory as Ivins at the U.S. Army Medical Research Institute of infectious Diseases USAMRIID, was called “a person of interest” in the investigation by then-Attorney General John Ashcroft.

The anthrax incident embarrassed experts in biodefense, who had spent years warning the U.S. government of the threat of such an attack.

“It’s a shame that people’s awareness about the kind of disruption and destruction that is possible came from someone working inside biodefense circles,” Monica Schoch-Spana of the Center for Biosecurity at the University of Pittsburgh said in a telephone interview.

CNN interviewed a man who identified himself as Tom Ivins, brother of the deceased. He confirmed his brother had committed suicide and said he himself had been interviewed by the FBI 18 months ago in connection with the investigation.

Alan Pearson, director of the Biological and Chemical Weapons Control Program at the Center for Arms Control and Non-Proliferation, urged the FBI to keep investigating.

“If Ivins was indeed responsible for the attacks, did he have any assistance? Did anyone else at the Army lab or elsewhere have any knowledge of his activities prior to, during, or shortly after the anthrax attacks?” Pearson asked.