(NECN: Jennifer Eagan, Dartmouth, Mass.) - Authorities searched several areas Friday near UMass Dartmouth.
Investigators spent much of the day combing through woods about nine miles away from the UMass Dartmouth campus, along Smith Neck Road.
Residents reportedly told officials about hearing loud booms in the area about a month or so ago.
Dartmouth resident John Arruda heard an explosion back around the end of March, just weeks before the Boston Marathon bombings, but when the bombing investigation led to Dartmouth, where surviving suspect Dzhokhar Tsarnaev went to UMass Dartmouth, Arruda called the feds.
"This was one of those things that shook the windows and everything," he says.
On Friday, ATF, along with state and local police, scoured the woods in several locations throughout Dartmouth, including an area along Smith Neck Road.
A source tells NECN that investigators were looking for signs of a test site, possibly where suspects would have tested explosives ahead of the bombing. There has been no word on whether anything was found.
"It's amazing what they can uncover," former FBI agent Tanya DeGenova says.
DeGenova says the backpack agents say they found in a Dartmouth landfill with empty fireworks inside is a key piece of evidence.
"Every stick of dynamite, every stick of firework, whatever, is very unique. It has a unique identity, so to speak, and they'll try to match that to whatever could be found on the remains of the bomb," she says.
Meanwhile, NBC News is citing sources who say that fingerprints and DNA found on bomb fragments do not match dead bombing suspect Tamerlan Tsarnaev's widow, Katherine Russell.