PITTSBURGH (KDKA) - Investigators face big challenges now as they probe deeper into the Boston Marathon bombings.
Now, they want to know why it happened and if others were involved.
Federal and state authorities are looking for answers now that one Tsarnaev brother is wounded and in custody. The other is dead after a shootout with police.
Retired FBI agent and LaRoche College professor Larry Likar said they'll want to know if more bombs are out there and if the brothers acted alone.
"Is there a movement? Is there more than just two, two individuals? What is the connection? How far does it go?" Likar said.
Likar said the bombs exploded during the Boston Marathon were not sophisticated and came from common materials.
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"Could they have done it on their own? It's possible. Probably more likely, when the older Tsarnaev went over to Russia, and spent some time in Slobovia Dagestan and Chechnya. He could have taken a course," Likar said.
Tamerlan Tsarnaev spent six months in his native Chechnya, last year.
"Perfect candidate. Started thinking about his own issues, plus, he had a religious background, from living over there for years in a hotbed of religious fundamentalism," Likar said.
His younger brother, Dzhokhar, is in serious condition, and unable to speak. If he survives, Likar believes, with help from his family, authorities may be able to find out why this happened.
"He's not that radicalized. He didn't want to sacrifice himself. Now, they say he may have tried to commit suicide at the end, though is that because of radicalization, or just sheer regret, humiliation, shame?" Likar said.
While there was lot of good police work, Likar credits the use of technology, like the infrared pictures of the younger Tsarnaev hiding in a boat, and the surveillance pictures that flooded the Internet, which eventually helped authorities identify the brothers.
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