TODAY | April 29, 2013
>> on this monday morning.
>> i'm matt lauer .
>> i'm savannah guthrie . new scrutiny of the suspect's mother.
>> she defended her sons from the very start and this morning we learn that she too has been part of investigations in her own country. national correspondent jeff is here with more on this.
>> lots of moving parts with this over the weekend. a source briefed on the case told nbc news russian authorities said they caught the mother and the older brother on a wire tap discussing jihad. this as the younger suspect starts his first week behind bars. he is waking up inside ft. devens, a prison for those with medical needs with a small cell with a sink, a shower, and a small window. his bed is bolted to the floor and the door made of steel with a small food slot. he is allowed one hour of recreation each day.
>> he is in complete lockdown and no contact with inmates or other staff.
>> now a source told nbc news, tamerlan was captured on a wire tap in 2011 talking to his mother on the phone about jihad.
>> why did they kill him? why?
>>> the same mother who proclaimed her sons' innocence. why didn't the russian share this with authorities until now?
>> they are careful about disclosing sources as our own intelligence is and there was a lot of suspicion. we will take the russian help as much as they're willing to give.
>> we are learning more about the bombs themselves. a new analysis shows the design seemed to follow instructions from inspire magazine published using low explosives consentist with commercial fireworks, adding shrapnel and a trigger system crafted from a toy car radio controller. also over the weekend, more tributes to the youngest victim of the attack. 8-year-old martin richard, his little league team painting his name on the field and draping his jersey over the fence, a heart felt reminder of how devastating this was. now the big question for investigators, did the suspects have any outside help? over the weekend, they combed a local landfill looking for the suspect's laptop, trying to trace their trail back and see who they have been talking to. they never found the laptop. the investigation continues of course.
>> thank you.