By Josh Levs and Ben Brumfield, CNN.
(CNN) – U.S. officials say there was female DNA found on at least one of the bombs used in the Boston Marathon attacks.
Female DNA was discovered on a fragment of the pressure cooker bombs used in the attack and investigators are trying to determine whose genetic material it was, law enforcement sources told CNN.
But one of the sources stressed the DNA could be from anyone who came in contact with the products used to make the bomb and it does not necessarily implicate anyone.
Investigators moved forward on another front in Rhode Island, searching the family home of Tamerlan Tsarnaev’s widow, Katherine Russell, for about 90 minutes on Monday.
Russell and her toddler daughter — Tamerlan’s child — have been staying at the North Kingstown home with her parents. Her attorneys were present during the search.
Agents left the home with items that included a black case and a clear plastic bag identified as DNA samples.
The second official warned that even if Russell’s DNA matches the female DNA on the pressure cooker, that does not necessarily prove she had anything to do with the preparation of the bomb. She — or any other female — might have come into contact with the cooker in the past.
Russell has said she was completely in the dark about her husband’s alleged plan. Her attorney said the news “came as an absolute shock.”
The two were married on June 21, 2010.
The double bombing near the finish line of the Boston Marathon killed three people and wounded more than 260. Twenty-three remained hospitalized on Monday. At least 14 people have needed amputations, according to medical officials.
Investigators searched a landfill in New Bedford, Massachusetts, in hopes of finding a laptop that could be relevant to the case. But the two-day effort ended without success, a U.S. law enforcement official told CNN Monday.
The FBI was following leads from Dzhokhar and others that his laptop was thrown in a dumpster and then picked up for disposal at a landfill.
The laptop might not be crucial to the investigation, the official added.
The suspects allegedly used low-grade explosives inside pressure cookers.
Investigators so far have found no evidence that the Tsarnaev brothers tested such bombs in the United States, the U.S. law enforcement official told CNN Monday.
CNN’s Deborah Feyerick, Bill Mears, Susan Candiotti, Ashleigh Banfield, Paula Newton, Drew Griffin, Dave Alsup, Carol Cratty, Brian Todd and Barbara Starr contributed to this report.
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