US scientist had purified anthrax

US Army scientist Bruce Ivins had sole custody of highly purified anthrax spores with "certain genetic mutations identical" to the poison that killed five people and rattled America in 2001, according to documents unsealed today in the government's investigation.

Investigators also reported tracing the type of envelopes used to send deadly spores through the post to the lab where Ivins worked.

The scientist, depicted in the newly released papers as deeply troubled, committed suicide last week as investigators were preparing to charge him with murder over the attacks.

The documents were released as the FBI held a private briefing for families of the victims of the episode, and officials said the agency was preparing to close the case.

More than 200 pages of documents were made public by the Federal Bureau of Investigation, virtually all of them describing the attempts to link Ivins to crimes that his lawyer has said he did not commit.

Senate Sergeant at Arms Terrance Gainer, who attended a briefing for congressional staff, said FBI agents had told the group there was no evidence that anyone else was involved.

According to one affidavit made public, Ivins submitted false anthrax samples to the FBI, was unable to give investigators "an adequate explanation for his late laboratory work hours around the time of" the attacks and sought to frame an unnamed co-worker.

He was also said to have been immunised against anthrax and yellow fever in early September 2001, several weeks before the first anthrax-laced envelope was received in the post.

The material describes at length painstaking scientific efforts to trace the source of the anthrax used in the attacks.

It says that in his lab, Ivins had custody of a flask of anthrax termed "the genetic parent" to the powder involved - a source investigators say was used to grow spores for the attacks on "at least two separate occasions".

Anthrax culled from the letters was quickly discovered to be the so-called Ames strain of bacteria, but with genetic mutations that made it distinct. Scientists developed more sophisticated tests for four of those mutations and concluded that all the samples which matched came from a single batch, codenamed RMR-1029, stored at a government laboratory where Ivins worked.

Ivins "has been the sole custodian of RMR-1029 since it was first grown in 1997", said one affidavit.

Powder from anthrax-laden letters sent to the New York Post and Tom Brokaw of NBC contained a bacterial contaminant not found in the anthrax-containing envelopes posted to Senators Patrick Leahy or Tom Daschle, the affidavit said.

Investigators concluded that "the contaminant must have been introduced during the production of the Post and Brokaw spores", the affidavit said.

Suggested Topics
Start your day with The Independent, sign up for daily news emails
Have you tried new the Independent Digital Edition apps?
News
ebooksAn unforgettable anthology of contemporary reportage
Latest stories from i100
Have you tried new the Independent Digital Edition apps?
Independent Dating
and  

By clicking 'Search' you
are agreeing to our
Terms of Use.

iJobs Job Widget
iJobs General

Recruitment Genius: Business Development Executive / Digital Marketing Executive

£26000 - £35000 per annum: Recruitment Genius: A luxury beauty house with a nu...

Recruitment Genius: Housekeepers - Immediate Start

£8 per hour: Recruitment Genius: This company are currently recruiting new exp...

Recruitment Genius: Head Concierge

£25000 - £28000 per annum: Recruitment Genius: This award winning Property Man...

Recruitment Genius: Content, SEO and PPC Executive

£20000 - £25000 per annum: Recruitment Genius: A fantastic opportunity has ari...

Day In a Page

On your feet! Spending at least two hours a day standing reduces the risk of heart attacks, cancer and diabetes, according to new research

On your feet!

Spending half the day standing 'reduces risk of heart attacks and cancer'
Liverpool close in on Milner signing

Liverpool close in on Milner signing

Reds baulk at Christian Benteke £32.5m release clause
With scores of surgeries closing, what hope is there for the David Cameron's promise of 5,000 more GPs and a 24/7 NHS?

The big NHS question

Why are there so few new GPs when so many want to study medicine?
Big knickers are back: Thongs ain't what they used to be

Thongs ain't what they used to be

Big knickers are back
Thurston Moore interview

Thurston Moore interview

On living in London, Sonic Youth and musical memoirs
In full bloom

In full bloom

Floral print womenswear
From leading man to Elephant Man, Bradley Cooper is terrific

From leading man to Elephant Man

Bradley Cooper is terrific
In this the person to restore our trust in the banks?

In this the person to restore our trust in the banks?

Dame Colette Bowe - interview
When do the creative juices dry up?

When do the creative juices dry up?

David Lodge thinks he knows
The 'Cher moment' happening across fashion just now

Fashion's Cher moment

Ageing beauty will always be more classy than all that booty
Thousands of teenage girls enduring debilitating illnesses after routine school cancer vaccination

Health fears over school cancer jab

Shock new Freedom of Information figures show how thousands of girls have suffered serious symptoms after routine HPV injection
Fifa President Sepp Blatter warns his opponents: 'I forgive everyone, but I don't forget'

'I forgive everyone, but I don't forget'

Fifa president Sepp Blatter issues defiant warning to opponents
Extreme summer temperatures will soon cause deaths of up to 1,700 more Britons a year, says government report

Weather warning

Extreme summer temperatures will soon cause deaths of up to 1,700 more Britons a year, says government report
LSD: Speaking to volunteer users of the drug as trials get underway to see if it cures depression and addiction

High hopes for LSD

Meet the volunteer users helping to see if it cures depression and addiction
German soldier who died fighting for UK in Battle of Waterloo should be removed from museum display and given dignified funeral, say historians

Saving Private Brandt

A Belgian museum's display of the skeleton of a soldier killed at Waterloo prompts calls for him to be given a dignified funeral