DesLauriers declined to speak publicly about this evidence. But news reports indicate that the FBI believes it may have recovered enough physical remains of the bombs to start the crucial business of reconstructing where parts came from and how they were assembled.
According to The New York Times, one of the pressure cooker scraps is inscribed “6L,” for six-liter capacity. The Spanish company Fagor is one firm that makes cookers identified with such a stamp. It sells 50,000 of them in the US every year, the Times reported.
At least some of the nails in the bombs were tiny, the size of picture-hanging nails or brads, according to NBC News.
A witness has provided WHDH, an NBC affiliate in Boston, with two photos that may help determine where and how one bomb was positioned, among other things.
The first photo shows a dark bag next to a mailbox and barricade along the marathon route. The second shows no bag, and injured people and debris blown about the scene.
“A man took the images from his office above Boylston Street and they show the moments right after one of the explosions,” wrote WHDH reporter Susan Tran.