Don Borelli, a former special agent for the FBI, talks about what is known of the two suspects in the Boston Marathon bombing so far, saying "we can't jump to conclusions yet" but "will be relying on our foreign intelligence partners."

Americans react very differently to gun violence versus terrorism. Chris Hayes discusses how that has applied to the Boston bombing with Donald Borelli, Hina Shamsi, and Esther Armah.

Former NCIS and ATF agent Robert McFadden and NBC News law enforcement analyst James Cavanaugh discuss the effect of premature - and outright false - reports on suspects and evidence that may have an impact on the Boston Marathon case.

CNBC's Scott Cohn reports the latest on the Boston bombings investigations; and Robert McFadden, Soufan Group and Bob Liscouski, Former Assistant Secretary for Homeland Security, provide perspective.

INSIDE EDITION speaks with former FBI counter terrorism expert, Don Borelli, to see how a pressure cooker can be turned into a bomb, like the one used in the Boston Marathon attacks.

Don Borelli, a former member of the FBI's joint terrorism task force examine the photos of the Boston bomb device.

There are still no hard answers, but lots of anguish and questions, a day after back-to-back explosions rocked America's oldest and most prestigious marathon. Douglas Herbert's panel discuss how Americans are dealing with a tragedy that Barack Obama is calling a cowardly "act of terror" - and look at how the rest of the world is reacting.

There are still no hard answers, but lots of anguish and questions, a day after back-to-back explosions rocked America's oldest and most prestigious marathon. Douglas Herbert's panel discuss how Americans are dealing with a tragedy that Barack Obama is calling a cowardly "act of terror" - and look at how the rest of the world is reacting.

Gwen Ifill talks with former deputy national security advisor Juan Zuarte and former senior FBI Official Don Borelli for their takes on the investigation and how authorities are sifting through evidence, as well as the president's characterization of the bombings as a terrorist attack.

Investigators are tracking down some two-thousand leads this morning after the twin explosions that occurred on Monday at the Boston Marathon. Officials are also poring over chilling photos showing the remnants of one of the detonated devices. Some of the images show wires, a battery and bits of what appears to be a circuit board. In addition, the FBI is now saying the second bomb was also in some type of metal container. This morning former Senior NCIS Official Robert McFadden weighs in on new investigation details regarding the Boston Marathon bombings...