"the public will play a critical role in identifying and locating them. Somebody out there knows these individuals as friends, neighbors, co-workers, or family members of the suspects."

"the word was out, regarding the suspects—we know how they looked like, and we knew that they lived in the city of Cambridge at one point...We knew that his house was under surveillance, and the Feds were all over the city of Cambridge…knowing that he, they lived there. So we were aware of that.”

The court filing does not give a date for the attempt, but cited sources who suggest that contact between the FBI and Tamerlan was ongoing for at least the three years prior to the bombing ( "FBI pushed elder Tsarnaev to be informer, lawyers assert," Boston Globe. The filing takes place as an MIT police sergeant, Sgt. Clarence Henniger, said in an interview last month that local law enforcement "knew" that Tamerlan Tsarnaev's "house was under surveillance" before the FBI asked the public to help identify him in a press conference on April 18, 2013, when Boston FBI head Special Agent Richard Deslauriers told the assembled press Sgt. Henniger is on the police force at MIT where MIT officer Sean Collier was found shot dead on the same night that the chase after the two brothers broke out, after a thus far anonymous man called the police saying he had been carjacked by the brothers.Henniger later clarified that the officers sharing this knowledge were "assuming" that the surveillance was directed at the Tsarnaevs, but had no first-hand confirmation from the FBI. The FBI has since said that the surveillance involved an entirely different case.It was revealed soon after the bombing and the capture of Dzhokhar, the younger brother, and the death of the older brother Tamerlan, that the FBI had interviewed Tamerlan multiple times in 2011, after a tip from Russian intelligence. The elder Tsarnaev brother was a Chechen national. CBS News reports that the FBI initially denied contacting Tamerlan.The Boston Globe reports that in the filing, Dzhokhar's lawyers "suggested that Tamerlan Tsarnaev could have misinterpreted his interactions with the FBI as pressure from the agency." The court filing said that the interactions could have “increased his paranoia and distress.”The AP reports that in the newly filed court papers, the defense team is asking for "records of all FBI contact with Tamerlan."Former Fox News journalist Ben Swann, soon after the bombing, said that certain aspects of the attack, such as the apparent concurrent bomb drill which was taking place moments prior to the explosions, should lead to questions over whether the Boston bombing was an FBI entrapment scheme gone awry. The startling charge by the Tsarnaev defense team, that Tamerlan may have been pressed to become an informant, suggests that the FBI knew far more about the brothers, and had closer contacts, than it is admitting.The court filing comes months after the mysterious death of one of Tamerlan's Chechen friends in Florida, Ibragim Todashev, who was killed during an FBI interview. The FBI says that, although unarmed, Todashev attacked, and was shot seven times including three shots in the back and one to the top of the head.RELATED:Ben Swann asks if Boston was FBI entrapment