WASHINGTON - The Boston Marathon bombing suspects managed to plan the attack, build bombs, transport them to the race site, set them off, escape and remain undetected for almost a week, authorities say.
A former top CIA covert operative says the Tsarnaev brothers, accused in the plot, were not amateurs.
"This is something that professionals with training do," Robert Baer tells WTOP.
Baer says a true sign of the suspects' expertise occurred when they were discovered and "knew how to stop police pursuit by throwing grenades out the window."
Building pressure-cooker bombs is no simple matter and the fact that all of the devices detonated when triggered indicates they practiced extensively, says Baer. He says the skill level required to make and deploy bombs reflects a high degree of capability.
"Having spent 30 years around explosives, I would have a very hard time with two explosive devices set to go off 12 seconds apart. You can't do this with an egg-timer," says Baer.
He says another tell-tale sign of comprehensive training was that the suspects ran at the sound of gunfire.
"The average person stands frozen when gunfire breaks out," Baer says. But "these guys reacted in the proper way when engaged by police."
He argues that, when looking at the totality of the suspects' behavior, it raises the question: "Why didn't they come up on the system?"
Because "the system is broken," Baer says.
The FBI, facing mounting allegations that it failed to follow up on Tamerlan Tsarnaev after repeated requests from the Russian government in 2011, says it only received one request, with which it complied. The bureau also stated it sought additional information but never got it.
When asked by WTOP about Russia's concerns about the older Tsarnaev brother's travel and associations with radical figures, an FBI spokeswoman deferred to a press release, which reads in part:
"The FBI did not find any terrorism activity, domestic or foreign, and those results were provided to the foreign government in the summer of 2011. The FBI requested but did not receive more specific or additional information from the foreign government."
The FBI acknowledged the Russian request was made "based on information that he was a follower of radical Islam and a strong believer, and that he had changed drastically since 2010 as he prepared to leave the United States for travel to the country's region to join unspecified underground groups."
The FBI says its agents, in response to the request, "checked U.S. government databases and other information to look for such things as derogatory telephone communications, possible use of online sites associated with the promotion of radical activity, associations with other persons of interest, travel history and plans and education history."
Additionally, the FBI says it "interviewed Tamerlan Tsarnaev and family members" and "did not find any terrorism activity, domestic or foreign."
When asked if it followed up with the now deceased Tsarnaev after he returned from a six-month visit to Dagestan in 2012, the FBI didn't respond.
Among the chief concerns for U.S. investigators is that Tamerlan Tsarnaev might have received significant terrorist training while there and connected with others who are still in or targeting the U.S.
As consternation about how much was known and when it was learned grows, the involvement of other U.S. agencies in the matter also has come to light.
Late Wednesday, a U.S. intelligence official told WTOP: "In late September 2011, the CIA received information from a foreign government on Tamerlan that was nearly identical to the information the FBI received in March 2011. The CIA then nominated him for inclusion in the watchlisting system and, given his status as a U.S. person, shared the information with the appropriate federal departments and agencies specifying that Tamerlan may be of interest to them."
The watchlist system is called the Terrorist Identities Datamart Environment (TIDE).
In addition to where the Tsarnaevs apparently learned to be expert bombers, the question of whether authorities were duped has arisen. Some U.S. intelligence sources suspect the older brother was more deeply involved in the terrorist culture than previously believed.
As investigators press on in their search for answers, it's becoming clear that the sheer volume of threat information pouring into FBI computers every day makes it a virtual impossibility to pick out and track each terror threat.
"The number of threats that we faced day to day when I was there, and I know they still face today, dwarfs what you see in the newspapers," says Philip Mudd, former deputy director of the FBI's National Security Branch.
"You're dealing with dozens of threats and maybe thousands of people of interest every day."
Mudd, who left the FBI in 2009, says counterterrorism analysts have to wade through email, phone, financial and travel activity records looking for connections. Because of the high volume of cases, they have to decide which ones they're going to pursue.
And that, he says, means "accepting that at this volume of business you've got to understand that you're going to drop an investigation."
Editor's note: Listen below to J.J. Green's interview with the superintendent-in-chief of the Massachusetts Bay Transportation Authority Transit Police Department.
Protecting commuters in Boston
WTOP's J.J. Green speaks with Joseph O'Connor, superintendent-in-chief of the Massachusetts Bay Transportation Authority Transit Police Department
Follow @WTOP on Twitter.
© 2013 WTOP. All Rights Reserved.