The FBI is now focusing on Katherine Russell Tsarnaev after federal officials investigating the Boston bombings have discovered radical Islamist materials on a computer belonging to the widow of Tamerlan Tsarnaev.
Katherine Russell Tsarnaev, 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 Katherine Russell’s computer, along with the presence of explosive residue throughout their home, have raised new questions about her 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 Katherine 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, Dzhokhar Tsarnaev, 19, had fled, setting off a massive manhunt that ended when he was discovered gravely wounded hiding in a boat.
Katherine 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.
Meanwhile, CNN reported that investigators inspecting Katherine Russell and Tamerlan 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.
However, it was established earlier this week that female DNA found one a piece of an explosive device used in the attacks did not match Katherine Russell’s, but rather belonged to a department store clerk where the Tsarnaev brothers 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 Katherine 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 Tsarnaev 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 Tamerlan Tsarnaev shared with Katherine Russell and their 3-year-old daughter, Zahara. Residue samples were found on the kitchen table, the kitchen sink, and the bathtub, the source said.
Katherine Russell’s 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 Katherine Russell’s parents, where Tamerlan 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.
Her lawyer says Katherine 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 Katherine 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”.
Katherine Russell met Tamerlan 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.
Tamerlan Tsarnaev died on April 19 following a shoot out with police in Watertown. Investigators say his younger brother, Dzhokhar Tsarnaev, hit him with a car as he fled the scene.