Was it a fingerprint?
But investigators quickly pointed out the DNA could have come from a female who touched the pressure cooker in a store, or from a woman who helped make the bomb.
Karima Tsarnaev, also known as Katherine Russell Tsarnaev, is the widow of bombing suspect number one, Tamerlan Tsarnaev.
On Monday, FBI agents visited her Rhode Island home and apparently took a DNA sample. But sources say that even if it is a match, that does not prove she helped make the bombs.
And now reports say investigators have another thread to follow, and this one leads to Canada, and to this guy, Canadian boxer turned terrorist William Plotnikov. Yes, a terrorist named Plotnikov.
That’s because Badenov was already taken.
A Russian newspaper is quoting Russian law enforcement sources who say Russian special forces killed Plotnikov and seven other suspected terrorists in Dagestan in July of last year. That was during time Tamerlan Tsarnaev was in the region.
Investigators cannot say for sure if the two ever met face-to-face, but besides being boxers, investigators say the two communicated with each other on a web site connected with the World Assembly of Muslim Youth, which is associated with the United Nations.
Pretty soon, these common threads will weave some answers about who, or what, was behind that deadly day in Boston.