5:00 p.m. eastern with the fbi, local police, the governor, the mayor and others. they'll tell us what they can at that time. in the meantime, your breaking news. >> i was told by one source this morning a boston law enforcement source that they believe they had a breakthrough of significant progress in the investigation. this source declined to be much more specific just said as the analysis continued, and we know the analysis was centered on video analysis, all the camera stuff turned in by local television stations, individuals, video and still photos. i was told there was a much better mood this morning and what they believe to be significant progress in the investigation, a turning point. that's how a boston law enforcement source described it to me. i spoke to a second source briefed on and based on my ranks with that source, i can't identify that source any further, but a reliable source someone getting detailed briefings on the progress in the investigation, that source said the breakthrough came from video analysis, much of the key video i'm told came from a department store right near the site of the second explosion, lord & taylor