Federal investigators are honing in on alleged Boston bombing mastermind Tamerlan Tsarnaev's widow Katherine Russell after reportedly discovering radical Islamist files on her laptop computer, according to reports.
Russell, 24, has maintained her innocence in the fatal attack that last month took the lives of three people and injured over 200, however the discovery of the al Qaeda magazine, "Inspire," along with the presence of explosive residue through their home have raised questions over whether she was involved.
Investigators said on Friday they believe Tamerlan Tsarnaev and his younger brother, Dzhokhar, likely made the bombs in Tamerlan's home on Norfolk Street in Cambridge, which he shared with Russell and their 3-year-old daughter.
CNN recently reported that investigators found traces of explosive residue in the kitchen sink, the bathtub and on a table.
Investigators said they are increasingly convinced that the ethnic Chechen brothers lifted their bomb designs from Internet postings by Islamic militants, though they substituted some components.
Soon after investigators released pictures of the suspected bombers and asked the public for help in identifying and locating the two men, Tamerlan communicated with his wife, said officials familiar with the investigation, who asked for anonymity when discussing sensitive information.
Law enforcement officials said the pair communicated after she saw the pictures of her husband and brother-in-law on television. Russell sent a text message to her husband, a national security source said.
Russell's lawyer declined to comment on Friday. He said earlier in the week that Russell spent many hours talking with officials and was eager to "provide as much assistance to the investigation as she can."
Officials took DNA samples from her after a woman's DNA was found on one of the bomb remnants. Other media have reported that the DNA on the bomb is not a match to Russell. The FBI declined to comment on the matter.
Ever since her husband was killed after a shootout with police, Russell, still dressing in long skirts and traditional Muslim head scarf, has been trying to stay out of sight while living with her parents in North Kingstown, Rhode Island. She has tried to distance herself from the man she married in June, 2010 at a mosque in Boston's Dorchester neighborhood.