case of the two brothers accused of bombing the boston marathon. Police say they have mounting evidence possibly linking the tsarnaevs to an unsolved triple homicide involving drugs and cash. This as... See More
case of the two brothers accused of bombing the boston marathon. Police say they have mounting evidence possibly linking the tsarnaevs to an unsolved triple homicide involving drugs and cash. This as we learn that the older brother tamerlan was buried in secret far from boston. And abc's gio benitez is he with the story. Good morning to you. The murders we're talking about HAPPENED ON SEPTEMBER 11th, 2011. It's been a cold case ever since but right now investigators are poring through the evidence and wait till you see what they're finding. This morning investigators tell abc news there is mounting evidence both tsarnaev brothers may is had something to do with the murders of thee plane. Brendan mess, eric weisman and rafael techen killing back in 2011 had no leads. They're looking for two assailants. It was graphic. All three men were killed by sharp wounds. The bodies covered in marijuana, 5 tu$,000 in cash nearby. Brendan had been roommates with tamerlan. The two reportedly even training partners for boxing and mixed martial arts. Now investigators tell abc news crime scene forensic evidence seems to point to the two tsarnaev records and cell phone records show they were in the area during the day of the murders. Dylan remembers his brother. S alwayhappy, had a smile on his face. Reporter: Investigators don't have enough evidence to charge the surviving tsarnaev brother, dzhokhar for the murders. It comes hours after tamerlan's body was secretly buried at a small muslim cemetery in virginia. The woman who said she would find the bur ial lot will remember. We need to remember our common humanity. Reporter: Back to that 011 murder case, sources say until more definitive dna testing is complete too early to consider bringing an indictment jens dzhokhar.
This transcript has been automatically generated and may not be 100% accurate.