Unanswered questions in New York, New Jersey bombings investigation

Ahmad Khan Rahami’s booking photo on Monday, Sept. 19, 2016.   

Union County Prosecutor's Office

As investigators continue probing the weekend bombings in New York City and Seaside Park, N.J., several key questions about Ahmad Khan Rahami, the chief suspect, remain. 

CBS News national security analyst Fran Townsend joined “CBS This Morning” Tuesday to discuss those unresolved issues, including finding where he allegedly constructed multiple bombs. 

“He made all these devices. He would have had to accumuluate stuff. he cell phone he acquired over a year ago,” Townsend said, referring to the phone that Rahami used as a detonator. “So where was he constructing this stuff, and why didn’t anybody notice?”

CBS News has learned the 28-year-old naturalized American -- who was born in Afghanistan -- had traveled to Afghanistan at least three times and visited Pakistan on at least one of those trips. While easy to point fingers at ISIS-inspired radicalization -- as the group typically claims responsibility for attacks -- Townsend said that information, along with others, suggest it is “equally likely” that he could have been “affiliated with Al Qaeda” or other international terror groups. 

According to sources, law enforcement officials have recovered a handwritten note and small notebook​ that belong to Rahami, which contain references to Osama Bin Laden and American-born jihadist cleric Anwar al-Awlaki. 

The mystery of Rahami’s motive may be harder to solve, as he refuses to cooperate with law enforcement officials. But Townsend said, as in prior investigations, authorities could try saying: “’Look, you don’t have to talk to us, but rest assured, if there are others out there with devices and you could help us prevent another terror attack or another explosion and you failed to, you will be charged with complicity in those future attacks and may have to face the death penalty if people are killed.’”

When asked if authorities had missed any red flags by not listing Rahami on the terror watch list -- despite his extended travels to countries of national interest  –Townsend admitted that she was worried.

“This is not the time to do it yet, but they’ll go back and look [at possible missed warning signs]. This was an extended travel, he had family over there,” Townsend said.

Townsend said officials are sure to trace back to his trips for clues, relying on cooperation with the Afghan and Pakistani intelligence services.

“Who did he meet with? Where did he go? Is this the trip where he was radicalized?” Because of course, investigators tell us that talking to people here, when he came back after that trip, he grew a beard, he seemed to be more anti-American, those sorts of clues,” Townsend said.