Al Qaeda magazine found on laptop of bomber's widow: Suspicion over FBI Tsarnaev's wife grows after radical Islamist files found along with traces of explosive residue throughout her home



Katherine Russell, 24, had al Qaeda's extremist Inspire magazine on her computer

Traces of explosives were found in bathtub, sink and on a table in her and Tamerlan Tsarnaev's Cambridge, Mass., home



Russell spoke to Tamerlan Tsarnaev in the hours after the FBI released images of him, but she will not reveal what they discussed

Fingerprints and DNA found on at least one bomb does not belong to her

Authorities 'skeptical about her insistence she had nothing to do with it'



New evidence: Tamerlan Tsarnaev's widow, Katherine Russell (pictured in 2007 mugshot) is under scrutiny after officials discovered radical Islamist files on her computer

Federal officials investigating the Boston bombings have discovered radical Islamist materials on a computer belonging to the widow of the deceased suspect, it has been revealed.

Katherine Russell, 24, has repeatedly claimed through her attorney that she knew nothing about the deadly April 15 bombings allegedly set off by her late husband, Tamerlan Tsarnaev, and his younger brother, Dzhokhar.

However, the discovery of al Qaeda’s Inspire magazine on Russell’s computer, along with the presence of explosive residue throughout their home, have raised new questions about Russell's possible involvement in the act of terror.

According to a government document obtained by NBC News, an analysis of the bombs used at the Boston Marathon and pipe bombs that the Tsarnaevs had allegedly thrown at police may have been built following instructions that appeared in an Inspire article titled: Make a Bomb in the Kitchen of Your Mom.

Officials have yet to determine whether the Islamist files found in Russell’s possession belonged to the 24-year-old mother, her late 26-year-old husband or a third party, a source told The Washington Post.

Tamerlan Tsranaev was shot dead in a gun battle with police four days after the marathon bombings when he and his brother allegedly carjacked a vehicle in a Boston suburb.

His younger brother, 18-year-old Dzhokhar Tsarnaev, had fled, setting off a massive manhunt that ended when he was discovered gravely wounded hiding in a boat.

Russell's attorney, Amato DeLuca, had previously said his client was kept in the dark about the deadly plot, and she was shocked to learn that her husband and brother-in-law were allegedly responsible for the attacks.

Staying silent: Katherine Russell, the wife of Boston bomber suspect Tamerlan Tsarnaev, leaves her lawyer's office with attorney Amato DeLuca on Monday. She has reportedly stopped cooperating with authorities



Meanwhile, CNN reported that investigators inspecting Russell and Tsranaev's home in Cambridge, Massachusetts, found traces of explosive residue in the kitchen sink, the bathtub and on a table.

Following his arrest, Dzhokhar Tsarnaev told police that he and his older brother built the pressure cooker bombs in the basement of the Cambridge residence.

'Incriminating': Officials say among the materials discovered on Russell's computer was al Qaeda's Inspire magazine

It was established earlier this week that female DNA found one a piece of an explosive device used in the attacks did not match Russell's, but rather belonged to a department store clerk where the siblings had purchased the pressure cookers.

In another development in the case, federal and state law enforcement officials accompanied by bomb-sniffing dogs scoured a wooded area near Dartmouth, Massachusetts, where Dzhokhar Tsarnaev attended college, in search of new evidence possibly related to the attacks.

According to witness accounts, the brothers may have tested explosives in the woods two weeks before the bombings

It was revealed earlier this week that Tamerlan Tsarnaev called his wife in the hours after the FBI released surveillance images of him and his younger brother .

But only Russell knows what was said in the conversation, as she has stopped cooperating with authorities over recent days, the New York Times reported.

Authorities are skeptical of her insistence that she played no role in the attack or in helping the brothers escape the authorities following the release of the photographs, the Times reported.

A source told CNN that the bombs were built in the apartment that Tsarnaev shared with Russell and their three-year-old daughter. Residue samples were found on the kitchen table, the kitchen sink, and the bathtub, the source said.



Her silence comes as sources told the newspaper that the fingerprints and female DNA found on at least one of the bombs did not belong to her. Authorities had taken a sample from her this week.

Spokesman Jason Pack confirmed that agents investigating the Boston bombings visited the North Kingstown home of Russell's parents, where Tsarnaev's widow has been staying since the attacks.

An official had revealed that female DNA was found on at least one of the bombs, although investigators haven't determined whose it is or whether it means a woman helped the two suspects.



Probe: Authorities visited her parents' home this week after female DNA was found on one of the bombs

Hiding out: Russell has been staying at her parents' North Kingstown, Rhode Island home, pictured

Her lawyer says Russell denies any involvement in the bombings, but authorities are still working to establish what exactly she knew - if anything - before or after the April 15 attacks.

On Wednesday, attorney Amato DeLuca insisted Russell 'will continue to meet with law enforcement, as she has done for many hours over the past week, and provide as much assistance to the investigation as she can'.

Russell met Tamerlan while she was a student at Suffolk University, according to her lawyer. She converted to Islam and they married in 2010 before having a daughter, now three.

Her husband was killed on April 18 following a shoot out with police in Watertown. Investigators say his younger brother hit him with a car as he fled the scene.

Suspect: Russell's husband Tamerlan Tsarnaev, pictured in 2010, died after a gun battle with police

Body: A vehicle believed to be carrying Tsarnaev's body backs into an underground garage at the Dyer-Lake Funeral Home in North Attleborough, Massachusetts. His family claimed his body on Thursday

Dzhokhar Tsarnaev was caught the following day as he was found hiding in a boat in a backyard.

Tsarnaev's cause of death could be released on Friday. The state medical examiner's office will go public with that information once the funeral home files a death certificate.

Russell, who has been living with her parents in North Kingstown, Rhode Island, learned this week that the medical examiner was ready to release his body and wanted it released to his family.

Department of Public Safety spokesman Terrel Harris said a funeral home retained by Tsarnaev's family picked up the remains. He said he had no more information about plans for the body.

Tsarnaev's uncle Ruslan Tsarni, of Maryland, said Tuesday night the family would take the body.

Changed: Russell, pictured left in high school and right following the bombings, met Tamerlan while she was a college student but dropped out when she fell pregnant. She converted to Islam for him



'Of course, family members will take possession of the body,' Tsarni said. 'We'll do it. We will do it. A family is a family.'

The April 15 bombing, using pressure cookers packed with explosives, nails, ball bearings and metal shards near the marathon's finish line, killed three people and injured more than 180 others.