Older bombing suspect's Russia trip, social media activity draw scrutiny

Older brother's Russia trip, social media activity draw scrutiny

(CBS News) As authorities wait to question 19-year-old Dzhokhar Tsarnaev, hospitalized in serious condition, about the Boston Marathon bombings, clues are pointing towards his now deceased older brother. Officials say 26-year-old Tamerlan Tsarnaev's recent travels to the Dagestan and Chechnya regions of Russia as well as his social networking activity are attracting a lot of attention. Bob Orr and Chalire D'Agata report.

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Bob Orr reports from Washington:

It's not clear if or when Dzhokhar can speak, but prosecutors do not necessarily need his statements to build a criminal case -- there is video evidence of him planting a bomb and police can testify he took part in the shootouts with officers in Watertown. But, the FBI still really wants to ask him about the plot and how it was put together.

The FBI still cannot find any evidence the brothers had any co-conspirators or any connections to larger terror group -- either foreign or domestic. Investigators of course are still looking.

From the evidence so far, officials believe the older brother was the key. His social networking activities suggest over the past two years he became increasingly interested in radical jihad. And investigators suspect he drew his 19-year-old brother into the plot.

In 2011, Russian authorities asked the FBI to investigate Tamerlan Tsarnaev because there were indications he had terror ties. The FBI did a background check and interviewed him. They did not find any terror connections nor any evidence that he had been in contact with any jihadists.

The FBI was satisfied that he posed no real danger at the time and he was not placed under surveillance.

Now, in hindsight, critics are asking if the FBI did enough, or if they missed a chance to stop the attacks.

Charlie D'Agata reports from Moscow:

Neighbors told CBS News on the phone that Tamerlan Tsarnaev stayed with his father or family members the whole six months he was in Russia in 2012, helping his father renovate the family business. Members of the local mosque said they recall seeing Tamerlan pray there, but there was nothing suspect about his time there.

Even today, the leader of a prominent Chechen rebel group came out and said they did not have any involvement in the attacks. So clearly, there are many questions left about what drove this man to commit this act.

The Russian government has offered help in the investigation if requested. But Russians are asking themselves the same questions here as in the U.S.: If the FSB specifically identified Tamerlan as a threat two years ago, why wasn't he stopped or at least more closely monitored in order to avert the attack?

Although a lot of blame has been placed on the FBI, a security analyst we spoke to today here said it was shocking that an individual on Russian intelligence radar was able to travel to and from the volatile region of Dagestan, through Moscow, for six months without anyone either stopping him or picking him up for questioning, when it appears he was identified as a potential threat to Russia.

(Boston bombing suspect Dzhokhar Tsarnaev remains in the hospital under critical but stable condition, reportedly unable to speak. Terrell Brown reports.)