Since the death of Tamerlan Tsarnaev and the capture of Dzhokar Tsarnaev, the American public has been able to stop holding its breath, confident that authorities have found those responsible for the Boston Marathon bombing and that justice will be served. Now, a DNA test on some of the bomb material found at the scene has uncovered female DNA, leading to authorities taking a harder look at the Tsarnaev’s female associates and family members.

A Wall Street Journal report on the revelation cites unnamed “U.S. officials” as stating the source of the DNA has not been determined. In fact, those same officials have said that the DNA may have come from many different sources, including store clerks or even bombing victims.

Soon after Tamerlan Tsarnaev was killed in a shootout with police, his life in the U.S. began to be revealed, including his wife, Katherine Russell, and his 3-year-old daughter. According to the Journal report, FBI agents this week took a DNA sample from Russell to see if it matches the DNA found on the bomb material. Russell has been staying with her parents since the bombing, and is being guarded by the FBI.

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